Simultanious Laser Beam Soldering of SMT-Components on MIDs with Fibre-coupled Laser Diodes. - Fröhlich, Thomas; Geiger, Manfred; Glasmacher, Matthias; Pucher, Hans-Jörg (Proceedings 2nd Int. Congress Molded Interconnected Devives - MID 96. Erlangen, 1996)
LFT Import::2019-08-05 (632)

Size Effect in the FE Simulation of Micro Forming Processes - Meßner, Arthur; Engel, Ulf; Kals, Roland; Vollertsen, Frank (Journal of Materials Processing Technology, 1994)
LFT Import::2019-07-16 (1974)

Size effects of CuZn37 brass foil in microforming - Li, He Zong; Dong, Xiang Huai; Wang, Qian; Shen, Yu; Diehl, Alexander; Hagenah, Hinnerk; Engel, Ulf; Merklein, Marion (Cailiao Kexue yu Gongyi/Material Science and Technology, 2011)
Uniaxial tensile tests and microbending experiments of brass foil specimens are performed to investigate size effects of metal foils in microforming process. The specimens are annealed at two different temperatures to obtain fine and coarse grain structure. In the paper, the springback angle in microbending process is predicted based on the classical plasticity theory and strain gradient theory. In uniaxial tensile tests, the increasing of material strength with decreasing foil thickness is observed, which indicates obvious presence of size effects for CuZn37 brass foils, especially for coarse grain specimens. In microbending experiments, obvious size-dependences of springback angle are observed, in which the springback angle of metal foils is increasing with foil thickness decreasing. The reasons for these size effects are discussed and the strain gradient hardening is important to microforming process.
LFT Import::2019-07-29 (1792)
Keywords: CuZn37 brass foil; Microforming; Size effect; Springback angle; Strain gradient

Size effects on springback behaviors due to plastic strain gradient hardening in microbending process of pure aluminum foils - Li, Hezong; Dong, Xianghuai; Shen, Yu; Diehl, Alexander; Hagenah, Hinnerk; Engel, Ulf; Merklein, Marion; et al. (Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2010)
In order to investigate the springback behavior of pure aluminum foils, scaled microbending experiments with different thicknesses ranging from 25μm to 500μm were carried out. In the experiments, it is observed that springback angle increases with decreasing foil thickness, which indicates obvious presence of size effects, and is attributed to plastic strain gradient hardening. So a constitutive model, taking into accounts both plastic strain and plastic strain gradient hardening, is proposed to analyze the microbending process of thin foils. The model is based on the relationship between yield stress and dislocation density, and is adopted to predict the springback angle after microbending both by analytical expressions and by FE simulation. It is confirmed that the predictions by using the proposed hardening model agree well with the experimental data, while those by using conventional elastoplastic model cannot capture such size effects. © 2010.
LFT Import::2019-07-02 (132)
Keywords: Microbending; Plastic strain gradient; Size effect; Springback

Sliding properties of excimer laser modified ceramic surfaces. - Becker, Wolfgang (Proceedings of the LANE 97, 1997)
LFT Import::2019-08-05 (693)

Smart FE-based tool design in cold forging - Andreas, Kolja; Kiener, Christoph; Engel, Ulf; Merklein, Marion (Advanced Materials Research, 2014)
In cold forging, the forming tool takes a key role. The present study focuses on the FE based analysis of different die sided leverages on the stress state in and the elastic behaviour of the forming tool. The results reveal a great influence of the workpiece material and the tool layout on the outcome of the forming process and the corresponding tool stresses.
LFT Import::2019-07-29 (2046)
Keywords: Cold forging; Design optimization; Tool

Solid freedom fabrication of ceramics parts from filler loaded preceramic polymers - Sindelar, T.; Buhler, P.; Niebling, Frank; Otto, Andreas; Greil, Peter (Solid Freedom Fabrication Symposium, 2002)
LFT Import::2019-08-05 (1705)

Some aspects concerning the physical models obtained using high performance composite material - Nedelcu, D.; Stöhr, Thomas; Ciofu, C.; Mindru, D (Proceedings 13th International Conference ModTech, 2009)
LFT Import::2019-08-05 (216)

Sonderverfahren zur Magnesiumverarbeitung - Merklein, Marion (Tagungsband MEFORM 2006, 29.-31. März 2006, Freiberg, 2006)
LFT Import::2019-08-05 (1303)

Spanablösung mit exakter Temperaturkontrolle - Schubart, Doris (Uni-Kurier-Magazin, 1998)
LFT Import::2019-07-16 (1619)

Specific characteristics of micro sheet metal working - Eckstein, Ralf; Geiger, Manfred; Engel, Ulf (SHEET METAL 1999, Proc. Of the Int. Conf. SheMet‘99, 27-28 Sep 1999, Erlangen, Germany, 1999)
None
LFT Import::2019-08-05 (1999)

Specific surface treatment by laser irradiation under liquid films - Roth, Stephan; Geiger, Manfred (ICALEO 2000, Proceedings of the 19th International Congress on Applications of Lasers & Electro-Optics, 2000)
LFT Import::2019-08-05 (800)

Specimen for a Novel Concept of Biaxial Tension Test? Design and Optimisation - Hußnätter, Wolfgang; Merklein, Marion; Geiger, Manfred (Advanced Methods in Material Forming, 2007)
Although in times of highest significance of process modelling and numerical simulation yield loci get more and more important, these characteristic values do only exist for a few materials primarily at room temperature. In this paper a novel concept of an experimental setup is introduced, with which plastic yielding of sheet metal can be examined also at elevated temperatures. The design of specimen is of great importance for the quality of experimental results, because stress conditions and with it forming behaviour are constituted. Thus, it must be optimized in consideration of stress singularities at corners and for achieving stress states, which are comparable to those of previous yield locus examinations. Most information and details can be obtained from finite element simulation. © 2007 Springer-Verlag Berlin Heidelberg.
LFT Import::2019-07-16 (1389)
Keywords: FE-simulation; sheet metal forming; yield locus

Specimen for a novel concept of the biaxial tension test - Geiger, Manfred; Hußnätter, Wolfgang; Merklein, Marion (Journal of Materials Processing Technology, 2005)
LFT Import::2019-07-16 (1191)
Keywords: Biaxial testing; FE-simulation; Sheet metal

Specimen´s Geometry Related Influences on Load-Bearing Capacity of Joining Aluminium and UHSS by Innovative Shear-Clinching - Hörhold, Réjane; Müller, Martin; Merklein, Marion; Meschut, Gerson (Journal of Materials Science Research, 2017)
LFT Import::2019-07-29 (2243)

Spring-back behaviour of thing metal foils in free bending processes - Diehl, Alexander; Engel, Ulf; Geiger, Manfred (4M 2005, Proceedings of the 1st International Conference on Multi-Material Micro Manufacture, 2005)
LFT Import::2019-08-05 (1181)

Stability of Bipolar Plate Materials for Proton-Exchange Membrane Water Electrolyzers: Dissolution of Titanium and Stainless Steel in DI Water and Highly Diluted Acid - Fiedler, Lena; Ma, Tien Ching; Fritsch, Birk; Risse, Jan Henning; Lechner, Michael; Dworschak, Dominik; Merklein, Marion; Mayrhofer, Karl; Hutzler, Andreas (ChemElectroChem, 2023)
The widespread use of proton exchange membrane water electrolyzers (PEMWE) is hindered by their high cost, of which a colossal factor is caused by the bipolar plates (BPP). In this paper, we investigate the stability of two BPP materials on-line with an optimized scanning flow cell setup coupled to an inductively coupled plasma mass spectrometer (SFC-ICP-MS), as well as scanning electron microscopy (SEM). The stability of currently used titanium and a cheaper alternative, stainless steel (SS) 316L, were characterized in deionized (DI) water and 0.5 mM H2SO4 to mimic the conditions at the BPP under operation. We show that the dissolution of Ti is negligible, whereas SS 316L degrades notably. Here, besides pH, the applied potentials play a crucial role. Nonetheless, even for the highest measured dissolution rate of SS 316L, the contamination in a full cell is estimated to remain below 1 ppm. This work illustrates the capabilities of on-line high-throughput stability tests for BPP materials and could therefore contribute towards optimization of cost-effective PEMWE.
CRIS-Team Scopus Importer:2023-09-29
Keywords: Cyclic voltammetry; Stability; Stainless Steel; Titanium; Water splitting

Stability of forming induced residual stresses in stainless steel components under mechanical load - Jobst, Andreas; Merklein, Marion (Manufacturing Letters, 2023)
Cold forward extrusion leads to the generation of residual stresses, which can have an advantageous or detrimental effect on the operating behavior of the formed components. In industrial practice, energy-intensive annealing steps are often used to remove unknown stress states and thus prevent unexpected failures. Residual stress-related knowledge can therefore help to save energy and resources. To be able to estimate the effects, not only sign and magnitude need to be known, but also the residual stress stability under typical operating loads. In this paper, stainless steel X6Cr17 (DIN 1.4016, AISI 430) is formed by forward rod extrusion at room temperature. The forming process leads to residual stresses in the formed components, which are subsequently subjected to mechanical testing. To represent different initial states, components with varied die opening angles are produced and tested. A modified 3-point bending setup is used to generate a defined tensile load stress in the part surface. The results show a behavior of the residual stresses, which is depending on the load magnitude, the initial stress state and the work hardening distribution in the part. While the number of cycles has an influence, the largest changes occur in the first stroke.
CRIS-Team Scopus Importer:2023-10-20
Keywords: Extrusion; Residual stress; Stability; Stainless steel

Stability of forming induced residual stresses in stainless steel parts at elevated temperature - Jobst, Andreas; Merklein, Marion (ICRS11 - 11th International Conference on Residual Stresses, 2023)

Stahlbleche Laserstrahl-Schneiden - Nuss, Rudolf; Gropp, Armin; Biermann, Stefan; Geiger, Manfred (Werkstatt und Betrieb, 1989)
LFT Import::2019-07-15 (439)

Stahl heiß in Form gebracht - Geiger, Manfred; Merklein, Marion; Lechler, Jürgen (Automobiltechnik in Bayern, 2007)
LFT Import::2019-07-16 (1461)

State of the Art in Laser Material Processing - Geiger, Manfred; Schultz, Markus; Hoffmann, Peter (ISEM 1992, State of the Art in Laser Material Processing. In: Proc. of the 10th International Symposium on Electromachining, 1992)
LFT Import::2019-08-05 (479)

Statistical Investigations on Friction Stir Welded - Giera, Artur; Merklein, Marion; Geiger, Manfred (Sheet Metal 2005, Proceedings of the 11th International Conference on Sheet Metal, 2005)
LFT Import::2019-08-05 (1163)

Steuerung von Blechmassivumformprozessen durch maßgeschneiderte tribologische Systeme - Löffler, Maria (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2019)
The industry is faced with a lot of requirements exemplary regarding a shortening of the process chains, a high functional integration or ecological aspects. Conventional sheet- and bulk forming operations are limited while facing such requirments. One method to meet the existing challenges is the combination of both process classes using sheet-bulk metal forming processes. Such a combination leads to a simultaneous occurance of conditions from sheet- and bulk forming operations during forming especially regarding the load conditions. These process characteristics leads to an uncontrolled material flow, in many cases yielding a reduced product quality. Within the thesis global methods to control the material flow using local adaptions of the tribological system were analyzed and evaluated regarding their effectiveness. To realizes this, the tribological mechanisms of modified tool- and workpiece surfaces were identified. These mechanisms can be used to guarantee the applicability of the results in sheet-bulk metal forming independently from the investigated parameter range within the thesi

Stochastische Simulation zur Werkzeuglebensdaueroptimierung und Präzisionsfertigung in der Kaltmassivumformung - Völkl, Ralf (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2008)
In cold forging the scatter of process parameters like workpiece material flow stress can show a high effect on the process properties e.g. tool life or workpiece accuracy. This book presents a simulation based method of modelling the influence of parameter scatter end using the model to optimize process design. In several case studies the potential of the method to increase tool life and workpiece accuracy is demonstrate

Strahlbearbeitung von Fließpresswerkzeugen - Integration von Strahloperationen in den Werkzeugherstellungsprozess - Andreas, Kolja; Merklein, Marion (wt Werkstattstechnik - Online, 2016)
LFT Import::2019-07-29 (2216)

Strahlformungskomponenten für das simultane Laserstrahllöten - Fröhlich, Thomas; Brickert, M.; Geiger, Manfred (Laser in der Elektronikproduktion & Feinwerktechnik, 2001)
LFT Import::2019-08-05 (860)

Strahlhomogenisierung auf der Basis von Mikrolinsenarrays - Stark, Markus; Völkl, Ralf; Zimmermann, M. (LEF 2005, Laser in der Elektronikproduktion & Feinwerktechnik, 2005)
LFT Import::2019-08-05 (1246)

Strategien für die Elektronikfertigung - Das Laserstrahl-Mikrolöten bietet große Potenziale im Bereich der Elektronikproduktion (Teil 1) - Fleckenstein, Marc; Bickert, Matthias; Fröhlich, Thomas; Abert, A.; Schneider, M. (Laser, 2001)
LFT Import::2019-07-15 (881)

Strategien zur Erweiterung der Prozessgrenzen bei der Innenhochdruck-Umformung von Rohren und Blechpaaren - Cojutti, Massimo (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2010)
The aim of this work was the development and validation of innovative process strategies by the hydroforming of tubes and sheet pairs to improve the achievable forming results. The investigations focused on the analysis of the material flow as a key factor for the improvement of the part properties. First the issue of sealing of the fluid by sheet hydroforming was addressed. The results of these investigations were used to improve the technology of hydroforming of tubes and sheet pairs in one tool and manufacture a complex hollow part. Further investigations focused on the development and the validation of a strategy for hydroforming double sheet parts made of inhomogeneous sheet pairs. In this strategy a counterpressure is applied to control the material flow during the proces

Strategies for residual stress adjustment in bulk metal forming - Franceschi, A.; Stahl, J.; Kock, C.; Selbmann, R.; Ortmann-Ishkina, S.; Jobst, Andreas; Merklein, Marion; Kuhfuss, B.; Bergmann, M.; Behrens, B. -A.; Volk, W.; Groche, P. (Archive of Applied Mechanics, 2021)
The family of bulk forming technologies comprises processes characterised by a complex three-dimensional stress and strain state. Besides shape and material properties, also residual stresses are modified during a bulk metal forming process. The state of residual stresses affects important properties, like fatigue behaviour and corrosion resistance. An adjustment of the residual stresses is possible through subsequent process steps such as heat treatments or mechanical surface modification technologies, like shot peening and deep rolling. However, these additional manufacturing steps involve supplementary costs, longer manufacturing times and harmful effects on the product quality. Therefore, an optimized strategy consists in a targeted introduction of residual stresses during the forming processes. To enable this approach, a fundamental understanding of the underlying mechanisms of residual stress generation in dependence of the forming parameters is necessary. The current state of the art is reviewed in this paper. Strategies for the manipulation of the residual stresses in different bulk forming processes are classified according to the underlying principles of process modification.
CRIS-Team Scopus Importer:2021-03-19
Keywords: Bulk forming; Cold forming; Hot forming; Manufacturing; Residual stress

Strength of self-piercing riveted joints with conventional rivets and rivets made of high nitrogen steel - Uhe, Benedikt; Kuball, Clara-Maria; Merklein, Marion; Meschut, Gerson (ESAFORM 2021 - 24th International Conference on Material Forming, 2021)

Stretch Forming of Ti-6Al-4V Hybrid Parts at Elevated Temperatures - Hafenecker, Jan; Rothfelder, Richard; Schmidt, Michael; Merklein, Marion (Sheet Metal 2021, 2021)
Keywords: Additive Manufacturing; Forming; Titanium

Strömungsbeeinflusstes Innenhochdruckumformen - Geiger, Manfred; Dal Bò, Paolo (Abschlusskolloquium des DFG Schwerpunktprogramms 1074, 2.-3. Mai 2005, Aachen, 2005)
LFT Import::2019-08-05 (1195)

Studienführer Maschinenbau 1999 - Kreis, Oliver; Geisel, Mark (Department Maschinenbau, FAU, 1999)
Mit diesem Studienführer können sich Studieninteressierte, Studierende und Dozenten über das Studium des Maschinenbaus der Friedrich-Alexander-Universität Erlangen-Nürnberg umfassend informieren. Berufsbild, Struktur und Ablauf des Studiums, Studieninhalte, Wahlmöglichkeiten, Kontaktadressen sowie die Rechtsgrundlagen werden ausführlich dargestell

Study of Microforging of Parallel Ribs from Metal Strip - Stellin, Tommaso; Van Tijum, Redmer; Merklein, Marion; Engel, Ulf (Material Forming - ESAFORM 2014, 2014)
The on-going trend in product miniaturization, together with the increasing quality and reduction of costs of micro-components, leads to the need of a robust process design, which might additionally avoid the occurrence of defects in the workpiece. Processes like microforming are affected by variations which can be foreseen but not totally mastered in the design stage. One approach is seen in an adaptive control system based on a metamodel processing the data of online measuring. This approach is grounded on in-depth knowledge based on correct and precise process modelling. This paper presents both experimental and simulative study of a microforging process, part of a more complex forming chain. It consists of six parallel ribs on metal strip. The ribs have a width of 250 μm and are spaced by a gap of 150 μm. The process has been studied by different punch forces, analyzing the final geometry of the workpiece. In particular the rib height is considered as critical to quality parameter. The simulations show reliable results that can be used for the design of the model interfacing measurement and control of the whole microforming process. © 2014 Trans Tech Publications, Switzerland.
LFT Import::2019-08-05 (2040)
Keywords: Microforging; Sheet-bulk metal forming; Stainless steel

Study of Micro Sheet Metal Working Processes - Geiger, Manfred; Eckstein, Ralf; Engel, Ulf (Production Engineering, 2001)
LFT Import::2019-07-15 (846)

Study of the mechanical properties of sheet metals drawn through drawbeads - Schmid, Harald; Merklein, Marion (Manufacturing Review, 2019)
The use of modern materials leads to a need for detailed knowledge of the material flow. Drawbeads are one common way to control serial forming processes. Although they are already well investigated, the effect on the resulting mechanical properties after a drawbead passage is not analysed in detail yet. This work is showing the influence of a drawbead geometry used in deep drawing on typical mechanical properties. Therefore, different sheet metal materials are preloaded in a modified strip drawing test with commonly used drawbeads. In testing, three different levels of pressure between 2.5 MPa and 7.5 MPa and of drawing speed between 10 mm/s and 50 mm/s are combined to nine variations and are examined. Afterwards, specimens are cut out by a laser cutting machine of the drawn strips. Those specimens are then tested with the use of an optical measurement system. Results are discussed in relation to blankholder pressure, drawing velocity and drawbead geometry to work out the main effects. Overall it can be stated, that variations of blank holder pressure and drawbead height lead to significant changes for the material properties. A variation of the drawing velocity in the observed range does not show significant effects.
CRIS-Team WoS Importer:2019-07-12

Suitability of the plasma plume position as a feedback signal for closed-loop process control in laser welding applications - Dietrich, Simon; Otto, Andreas; Schmidt, Michael (Proceedings of the 4th International WLT-Conference on Lasers in Manufacturing, 2007)
LFT Import::2019-08-05 (1408)

Surface characterisation in forming processes by functional 3D parameters - Weidel, Stephan; Engel, Ulf (International Journal of Advanced Design and Manufacturing Technology, 2006)
LFT Import::2019-07-16 (1320)

Surface characterization with regard to the tribological behaviour of sheet metal in forming processes - Popp, Uwe; Engel, Ulf; Geiger, Manfred (SHEET METAL 1999, Proc. Of the Int. Conf. SheMet‘99, 27-28 Sep 1999, Erlangen, Germany, 1999)
None
LFT Import::2019-08-05 (2000)

Surface modification of additively manufactured parts by forming - Hafenecker, Jan; Kuball, Clara-Maria; Rothfelder, Richard; Schmidt, Michael; Merklein, Marion (ESAFORM 2021, 2021)
Additive manufacturing (AM) has many advantages compared to conventional processes. Of particular interest is the tool-less manufacturing of components, which allows one component to differ from the next completely and has the possibility of producing complex geometries. At the same time, however, AM has deficits such as long production times, low production tolerances and low surface qualities compared to conventional processes. Therefore, a finishing process using machining is often necessary, which extends the manufacturing time and produces waste. Thus, the avoidance of machining rework is of high interest, especially with expensive materials such as stainless steel or titanium. One approach to avoid machining processes is to use forming technology. By applying a forming operation, surfaces can be smoothened and geometrical aspects can be defined more sharply. Especially for functional surfaces, this procedure is favorable because of the work hardening, which in turn increases the strength of the material. Using the example of laser-based powder bed fusion (PBF-LB) followed by a cup backward extrusion process, two materials, which are frequently used in AM are investigated. On the one hand, the titanium alloy Ti-6Al-4V, as a material with low machinability and low formability at room temperature, and the stainless steel 316 L. Compared to Ti-6Al-4V, 316 L has a higher formability. Cylinders are built using PBF-LB and then formed to smoothen the surface and achieve a higher geometrical accuracy concerning edges. Formed, additively made parts have a more defined geometry, namely sharp edges and a surface roughness reduced by up to 90 %
Keywords: Additive Manufacturing; Forming; Surface Modification

Surface modifications for adaption of tribological conditions in sheet-bulk metal forming processes - Löffler, Maria; Andreas, Kolja; Engel, Ulf; Weikert, Tim; Tremmel, Stephan; Wartzack, Sandro; Stangier, Dominic; Tillmann, Wolfgang; Merklein, Marion (Proceedings THE "A" Coatings, 2016)
Keywords: Sheet-bulk metal forming; Coatings; Friction

Surface structuring of forming tool surfaces by high feed milling - Freiburg, D.; Löffler, Maria; Merklein, Marion; Biermann, D. (2017)
LFT Import::2019-08-05 (2255)

Surface Texturing of Ceramics to Reduce Friction in Forming Processes - Neudecker, Thomas; Hinsel, Christian; Engel, Ulf (Proceedings of the Simposium on Computational an Experimental Methods in Mechanical and Thermal Engineering, 1998)
LFT Import::2019-08-05 (1612)

SVL-Concept - Current State of Progress in Predicting Performance and Reliability of Cold Forging Tools - Engel, Ulf; Völkl, Ralf; Arbak, Murat (Conference Proceedings ICIT 2003 4th International Conference on Industrial Tools, Bled Celje, Slovenia, April 8th-12th, 2003)
LFT Import::2019-08-05 (940)

SVL-Concept? Experiences in prediction of tool life and tool reliability in cold forging - Engel, Ulf; Völkl, Ralf (Advanced Technology of Plasticity, Proceedings of the 7th ICTP, 2002)
LFT Import::2019-08-05 (1684)

Systematic exploration of the L-PBF processing behavior and resulting properties of β-stabilized Ti-alloys prepared by in-situ alloy formation - Huber, Florian; Papke, Thomas; Kauffmann, Constantin; Rothfelder, Richard; Krakhmalev, Pavel; Merklein, Marion; Schmidt, Michael (Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2021)

Systematische Untersuchung zur Blechumformung von Hybridbauteilen - Hafenecker, Jan (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2024)
Die Kombination von Umformtechnik und additiver Fertigung ermöglicht die Herstellung von Hybridbauteilen, die die Vorteile beider Verfahren nutzen, um somit industriellen Trends entgegenzuwirken, die konventionelle Fertigungsansätze an ihre Grenzen treiben. Die auf den Blechen additiv aufgebrachten Funktionselemente beeinflussen das Materialverhalten während der Umformoperation und begünstigen ein früheres Materialversagen in Form von Rissbildung. Um dennoch das volle Potential von Hybridbauteilen, bestehend aus Blechen und additiv gefertigten Funktionselementen, auszuschöpfen, werden im Rahmen dieser Arbeit die Wirkmechanismen beim Tiefziehen von Hybridbauteilen mit bis zu 21 Funktionskörpern erarbeitet. Dafür wird der Herstellungsprozess ganzheitlich untersucht, indem eine Prozessführungsstrategie des genutzten pulverbettbasierten Laserstrahlschmelzens erarbeitet wird, die mechanischen Eigenschaften von Blech- und Additivkomponente vergleichend charakterisiert werden und abschließend Forschungshypothesen bezüglich der Einflussmechanismen geprüft werden. Die unterschiedlichen Herstellungsverfahren resultieren in unterschiedlichen Mikrostrukturen und demzufolge mechanischen Eigenschaften, die bei der Modellierung und Umformung der Hybridbauteile beachtet werden müssen. Bei der Gestaltung der Hybridbauteile ist darauf zu achten, dass die Durchmesser der Funktionselemente gering gewählt werden, die Platzierung in unkritischen Bereichen und gleichmäßig verteilt erfol

System for the automatic correction of sheet metal bending angles by means of laser beam forming - Hagenah, Hinnerk; Geißdörfer, Stefan (The 9th International Conference on Metal Forming ESAFORM, 2006)
LFT Import::2019-08-05 (271)

System Technology and Data Preparation for Automated Laser Assisted Stacking of Metal Foil Contours - Prechtl, Martin; Pursche, Lars; Otto, Andreas (LANE 2004, Proceedings of the 4th International Conference on Laser Assisted Net Shape Engineering, 2004)
LFT Import::2019-08-05 (1054)

System- und Prozeßtechnik für das simultane Löten mit Diodenlaserstrahlung von elektronischen Bauelementen - Hierl, Stefan (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2004)
The electronic production requires a powerful and economic joining technology which copes with the trends to miniaturisation and integration. But more and more established soldering techniques border their limits e.g. when solder joints are difficult to access or when substrates or electronic devices have a low thermal resistance. The simultaneous laser soldering offers a solution for such joining tasks. Therefore the aim of the Dr.-Thesis is to provide the basics of the system and process technology for this joining method. A prototype of a laser soldering machine was developed, which mainly consists of a soldering head with four diode lasers and an adaptive beam shaping for generating variable light lines. The investigations have shown that the simultaneous laser soldering is suited to join SMDs of different shapes and sizes both on standard substrates and on 3-D MID

System- und Verfahrensoptimierung für die schnelle Herstellung von Funktionsteilen durch Laserabtragen - Schubart, Doris (Werkstattstechnik, 1998)
LFT Import::2019-07-16 (1620)

Tailored heat treated accumulative roll bonded aluminum blanks: failure under bending stresses - Nguyen, H.; Boehm, W.; Tsoupis, Ioannis; Göken, Mathias; Höppel, Heinz Werner; Schmidt, Christian; Hausöl, Tina; Ruppert, Mathis; Merklein, Marion (Production Engineering, 2016)
Ultrafine-grained accumulative roll bonded (ARB) sheet metals of aluminum alloys have a high potential for lightweight construction. The mechanical properties can be enhanced regarding strength and ductility by the combination of ARB and a local heat treatment according to the Tailor Heat Treated Blanks technology. The present investigation focuses on the failure behavior of ultrafine-grained ARB blanks. Due to the low formability of these high-strength ARB metals, a detailed understanding of the failure mechanisms is essential. For this purpose, an established approach to determine the different stages of damage of the material for conventional materials is now applied to multilayered aluminum in the as-received and heat-treated condition. In this context, air bending tests are used to qualify and quantify the bending and forming behavior of ARB sheets of AA1050A and AA6016 aluminum alloys.
Keywords: Tailor Heat Treated Blanks (THTB); Ultrafine-grained microstructure (UFG); Failure; Formability; Bending; Accumulative roll bonding (ARB)

Tailored heat treated accumulative roll bonded aluminum blanks: Microstructure and mechanical behavior - Maier, Verena; Hausöl, Tina; Schmidt, Christian; Böhm, Wolfgang; Hung Nguyen,; Merklein, Marion; Höppel, Heinz Werner; Göken, Mathias (Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2012)
Aluminum alloy AA6016 was accumulative roll bonded up to eight cycles and investigated regarding formability by bending tests. Due to the limited bendability of accumulative roll bonding (ARB) processed materials, a tailored laser heat treatment was performed along the bending edge before forming. This tailored laser heat treatment causes a local recrystallization and recovery of the bending samples at the deformation zone, which locally increases ductility and allows higher bending angles achievable with lower forming forces. Between the recrystallized heat treated zone and the unaffected ultrafine-grained (UFG) base material, a gradient in grain size with a bimodal region is formed. This observed microstructural profile is confirmed by local mechanical testing measuring the hardness and strain rate sensitivity by nanoindentation techniques.
WW1::947

Tailored Heat Treated Blanks applied on car body parts under quasi-series conditions - Merklein, Marion; Staud, Detlev; Vogt, Uwe (International Journal of Microstructure and Materials Properties, 2008)
LFT Import::2019-07-29 (1507)

Tailored Heat Treated Profiles - Enhancement of the Forming Limit of Aluminum Profiles under Bending Load - Merklein, Marion; Lechner, Michael; Schneider, Thomas; Plettke, Raoul (Key Engineering Materials, 2012)
Aluminum profiles are well-established components in lightweight constructions. However, these profiles have a small forming capability in comparison to steel profiles, which leads to a limitation in their application. Within this paper a new and innovative approach for the enhancement of the forming limit of aluminum profiles under bending load called Tailored Heat Treated Profiles (THTP) is presented. With THTP the mechanical properties of the material are locally modified by a short-term heat treatment. By this local modification the material flow during the following cold bending operation can be influenced. For the design of the heat treatment layout, the correlation between the heat treatment parameters and the material properties has to be investigated. Tensile specimens were cut out of the profile and were subsequently completely heat treated with a laser. The changes of the mechanical properties caused by the heat treatment were analyzed by tensile tests. However, with a complete softening of the profile, the formability could not be improved. To increase the formability a local heat treatment, which leads to partial softening of the profile, has to be investigated. In order to characterize the heat-affected zone (HAZ) of the laser treatment, thermal camera and microhardness measurements were carried out. Appropriate heat treatment layouts have to be found to enhance the forming limit. Different layout strategies were developed and afterwards validated by the heat treatment and forming of profiles. This paper will present the findings of this investigation and show that THTP can be used to improve the formability of aluminum profiles for bending operations. © (2012) Trans Tech Publications.
LFT Import::2019-07-29 (1801)
Keywords: Aluminum profiles; Bending; Enhancement of formability; Tailored heat treatment

Tailored Heat Treatment Strategy for the Orbital Forming of Functional Components from EN AW-7075 - Hetzel, Andreas; Biburger, Michael; Lechner, Michael; Merklein, Marion (Springer, 2024)
The application of forming operations instead of conventional cutting processes is a practical approach to increase material efficiency and functional integration, thus addressing lightweight design. In this context, the innovative process class of Sheet-Bulk Metal Forming is presented, which combines the advantage of bulk and sheet metal forming. One of the assigned processes for the manufacturing of functional components with different form elements is orbital forming. Within previous investigations, the major challenge could be identified as a control of the material flow. Since process parameters, like an increased forming force, are not sufficient to avoid process failures in form of wrinkles, other measures have to be taken into account. Especially when applying precipitation hardenable aluminum alloys, one possibility is the application of a local short-term heat treatment. By locally reversing the hardening effect of the precipitation clusters, the interaction between softened and still hard areas can be used to attain the desired material flow. Although this procedure is established for conventional sheet metal forming processes and was furthermore investigated for the orbital forming of components from the aluminum alloy EN AW-6016, the influence on the forming of high-strength aluminum from the 7xxx-series is still content of current research. Especially due to a reduced formability at room temperature, this alloy is predominantly formed at elevated temperatures. By introducing the established method of a local short-term heat treatment on 7xxx alloys, a contribution towards a possible forming at room temperature is made. Therefore, this work focuses on the development of a tailored heat treatment strategy to control the material flow during orbital forming. Specimens out of the high-strength aluminum alloy EN AW-7075 with a thickness of 2.0 mm in condition T6 are heat-treated and consequently cold formed. The results are quantified by a geometry-based analysis. The resulting strain distribution is used to verify the material flow proportions.<br
Keywords: Aluminum alloy; Local short-term heat treatment; Orbital forming

Tailored material flow in pin-extrusion of sheet metal under varying material and geometric conditions for enhanced joining technology applications - Römisch, David; Kraus, Martin; Merklein, Marion (International Journal of Material Forming, 2025)
Pin structures extruded from the sheet metal plane have numerous industrial applications. For instance, they can be used in bulk microforming to solve handling difficulties or in joining technology to connect dissimilar materials to overcome challenges of different chemical, thermal and mechanical properties of materials. Due to the absence of material flow restrictions in the direction of the sheet metal plane, pin extrusion is affected by numerous process-, workpiece- and tool-related parameters, which have a huge impact on the material utilization and the obtainable pin geometry. Within the scope of this study, a combined numerical-experimental research approach is used to analyze the influence of the material and its condition on the achievable pin height and the occurrence of the mostly undesired funnel formation at high punch penetration depths. For this purpose, elastic-ideal plastic and elastic-real hardening model materials are first investigated numerically, which are subsequently validated and verified in experiments by using the materials Cu-OFE and DC04 on a laboratory scale. Based on the results, recommendations for the material selection and its properties are derived in order to maximize the material utilization. In addition, a pin joining process with locally modified extrusion conditions to increase the load-bearing capacity, especially under axial load, is being investigated with DP600 and AA 6014-T4. This process is a new type of two-stage mechanical joining process without an auxiliary joining element in which pin structures extruded from the sheet metal plane are used to join dissimilar materials in a subsequent step. In this work, test specimens are locally pre-punched before pin extrusion to create an enhanced pin geometry in order to achieve an improved undercut in the subsequent joining process. As a result, a new type of pin geometry was realized and investigated, which shows a significant increase of up to 82% in load-bearing capacity under axial load compared to the existing reference pin geometr
Keywords: Pin extrusion; Material flow; Pin-joining; Sheet metal

Tailored modifications of amorphous carbon based coatings for dry deep drawing - Merklein, Marion; Schmidt, Michael; Tremmel, Stephan; Andreas, Kolja; Häfner, Tom; Zhao, Rong; Steiner, Jennifer (Dry Metal Forming Open Access Journal, 2016)
Avoiding negative effects of conventional lubrication in forming operations stimulates research on lubricant-free sheet metal forming. Without lubricants, the direct contact between tool and workpiece leads to intensive interaction in terms of increasing friction and wear. Especially, when forming aluminum alloys, adhesion is detected as main wear mechanism propagating already at the initial contact between tool steel and sheet material. Thus, surface modifications need to be developed to substitute the functions of conventional lubricants. Former studies revealed that amorphous carbon based coatings improved the tribological conditions. Depending on the specific coating type adhesion and friction could be significantly reduced. Besides achieving a lower level of friction, a control of material flow is necessary to improve the forming results in deep drawing processes. Thus, there is a need for contact zones with higher and lower friction to locally accelerate or restrict the flow of the sheet material. In order to achieve these tailored tribological conditions a broad range of surface modifications needs to be developed and evaluated in a process-like environment. The tribological behavior is affected by coating properties and structure. By varying gas flow and ratio for a-C:H coatings the relationship between deposition parameters and coating properties are investigated. A further approach to realize a broader range of friction coefficients is the laser based texturing of coated tools. Additionally, a laser based heat treatment is investigated to control the sp2/sp3 ratio of ta-C coatings to affect friction and wear mechanisms. The tribological behavior of the investigated surface modifications is analyzed in ring-on-disc and flat strip drawing tests. A surface characterization is performed to identify about the wear mechanisms. Based on the modifications of a-C:H and ta-C coatings a correlation between chemical and mechanical properties and the tribological behavior in contact with zinc-coated deep drawing steel and aluminum alloys is found.
Keywords: Dry Deep Drawing; Tribology; Carbon Based Coatings; Laser Based Modification

Tailored multi-material systems with thickness distribution by orbital forming - Harms, Arnold; Wituschek, Simon; Lechner, Michael; Merklein, Marion (CIRP Annals - Manufacturing Technology, 2025)
The utilization of multi-material systems is becoming increasingly relevant for future production technologies with regard to lightweight design and higher functional integration. Furthermore, improvements demand for new approaches that involve the integration of local material accumulation and a joining operation in a single step using an orbital forming process. The investigations are carried out on the basis of a demonstrator joining a steel ring and an aluminum blank. This involves the analysis of the mechanisms for joint formation, the identification of process limits, and the determination of a process window for the manufacturing of an adequate hybrid component.
CRIS-Team Scopus Importer:2025-04-18
Keywords: Mechanical joining; Multi-material systems; Orbital forming

Tailored solutions in mechanical engineering - Merklein, Marion; Lechner, Michael (Public Service Review, 2012)
LFT Import::2019-07-29 (1829)

Tailored Surfaces in Sheet-Bulk Metal Forming - Vierzigmann, Ulrich; Merklein, Marion; Engel, Ulf (Proc. 4th International Conference on Tribology in Manufacturing Processes (ICTMP), 2010)
LFT Import::2019-08-05 (288)

Tailored tempering – FE-Simulation of manufacturing components with local adjusted mechanical properties - Svec, Thomas; Merklein, Marion (Steel Research International, 2012)
LFT Import::2019-07-29 (1797)

Tailoring material properties in forming technology by a local heat treatment - Merklein, Marion; Graser, Matthias; Degner, Julia; Lechner, Michael; Herrmann, Jürgen (Advanced Metal Forming Processes in Automotive Industry, 2016)
LFT Import::2019-08-05 (2177)

Tailoring Material Properties of Aluminum by Local Laser Heat Treatment - Merklein, Marion; Böhm, Wolfgang; Lechner, Michael (Physics Procedia, 2012)
The local laser heat treatment of precipitation hardenable aluminum alloys enables the tailoring of the materials properties and the manufacturing of lightweight and crash-proof components for the body in white. For conventional aluminum sheet metals and profiles the formability is enhanced by an indirect approach. Thereby specific parts of the products are softened in order to improve the material flow towards crack critical areas during the forming operation. For innovative high-strength aluminum sheet metal with nanocrystalline grain structure produced in the Accumulative Roll Bonding process in addition to the indirect approach a direct enhancement of the formability by recrystallization effects is possible.
EAM Import::2019-03-12

Tailor-Made Forging Tools by Laser Metal Deposition - Junker, Daniel; Hentschel, Oliver; Schmidt, Michael; Merklein, Marion (Key Engineering Materials(2015), 2015)
The desire for individualized products forces the companies to a great diversity of combinable parts. This way, the clients can compile their personalized product. As this trend is not just limited on visual parts but also for functional components, laser additive manufacturing of metals is used more and more often in manufacturing. To bring more additive manufacturing into mass production, Laser Beam Melting and Laser Metal Deposition will be qualified for the use in tool manufacturing within the Bavarian research association "ForNextGen - Next Generation Tools". The first subproject within this research association investigates the potential of Laser Metal Deposition in the production of hot and cold forging tools. Within initial tests optimized process, parameters for the processing of the hot-work steel 1.2709 are determined by single welding beads. The achieved density and the inner structure are analyzed within cubes that were built with the investigated parameters. As forging tools are usually made of high-carbon tool steel, the processing of materials with a rising percentage of carbon will be part of further investigations.
LFT Import::2019-08-05 (2111)
Keywords: Additive manufacturing; Forging tool; Graded structures; Highcarbon steel welding; Tool manufacturing

Tailor Quenched Blanks - Merklein, Marion; Lechner, Michael; Kuppert, Andreas (Danish-German Aerospace Collaboration Kick-Off, 2013)
LFT Import::2019-07-29 (1944)

Tailor Welded Blanks und Patwork Blanks mit Hochdruck in Form bringen - Tolazzi, Massimo; Lamprecht, Klaus; Blankl, Andreas; Cojutti, Massimo (Maschinenmarkt, 2008)
LFT Import::2019-07-29 (1504)

Targeted influencing of the mission-relevant component properties of cold-forged gearwheels - Rohrmoser, Andreas; Kiener, Christoph; Schubert, Dominik; Hagenah, Hinnerk; Drummer, Dietmar; Merklein, Marion (Konstruktion, 2019)
Cold forging offers the potential to produce ready-to-use gears in a process suitable for series production. In material pairing with a plastic gearwheel, the component properties of the steel gearwheel have a decisive effect on the wear behaviour and service life of the pairing. This results in requirements for the component properties that must be taken into account when designing the cold forging process. In the context of this article, the improvement of the resulting running-in behaviour of a steel-polyamide gear pairing by targeted measures within the design of the cold forging process of the steel pinion is investigated.
CRIS-Team Scopus Importer:2021-04-20

Task Specific Registration Algorithmy within the Closed Loop Control of Laser Forming Processes - Geiger, Manfred; Hagenah, Hinnerk; Hutterer, Angelika (Production Engineering, 2005)
LFT Import::2019-07-16 (1186)

Technik – die prägende geistige Errungenschaft unserer Zeit. Festvortrag zum dies academicus aus Anlass des 261. Jahrestages der Gründung der Friedrich-Alexander-Universität Erlangen-Nürnberg am 4. November 2004 - Geiger, Manfred; Kreis, Oliver; Gaus, Ingrid (FAU, 2005)

Technische Keramik in der Kaltmassivumformung? Verbesserung der Oberflächenqualität und Maßhaltigkeit - Arbak, Murat; Putz, Alexander; Engel, Ulf; Geiger, Manfred (Maschinenbau in Bayern, 2006)
LFT Import::2019-07-16 (1281)

Technische Keramik in der Kaltmassivumformung - Werkzeugauslegung mit Berücksichtigung der thermischen Effekte - Arbak, Murat (3D-Erfahrungsforum Innovation im Werkzeug- und Formenbau, 2007)
LFT Import::2019-07-16 (1463)

Technologieorientierte Bahnplanung für die 3D-Laserstrahlbearbeitung - Backes, Frank (1997)
The aim of the research work was the development of an technology orientated path planning algorithm for 3D laser processing. The algorithm allows for an automatical off-line generation of machine programs for laser cutting and welding. Besides a CAD model of the workpiece a model of the robot is used, which represents the geometry and the kinematic properties of the robot. Programs can be created for gantries with 5 axes and robots with 6 rotational axes. By making use of path planning strategies, which were especially developed for 3D laser processing, optimised machine programs can be generated off-line with respect to path velocity and the dynamic behaviour of the robot. Since the time consuming teach-in procedure can be avoided, the algorithm leads to a significant reduction of the programming time and to an increased machine utilisation. The advantages of the algorithm have been demonstrated by performing several processing tasks. One typical example is the cutting of deep drawn sheet metal parts, as it is carried for prototype manufacturin

Technology Oriented Off-Line Programming for 3D Laser Machines. - Backes, Frank (Proceedings of the LANE 97, 1997)
LFT Import::2019-08-07 (689)

Technology oriented Off-line programming for 3D Laser Processing. - Backes, Frank; Geiger, Manfred; Franke, Volker (Technical Papers of the North American Manufacturing Research Institution, 1996)
This paper describes the concept and basic algorithms of a flexible off-line programming system which has been specially developed for 3D laser processing tasks such as cutting or welding. The most important feature of the system is a technology oriented path planning, which simultaneously considers the part geometry, the particular process parameters and the properties of the machine tool.
LFT Import::2019-08-05 (585)
Keywords: 3D Laser Processing; Off-Line Programming

Technology Oriented Off-Line Programming for 3D Laser Processing of Sheet Metal Parts. - Backes, Frank (International Conference on Sheet Metal SheMet 97. Belfast, United Kingdom, 1997)
LFT Import::2019-08-05 (688)

Technology Oriented Off-line Programming of 3D-Laser Machines - Geiger, Manfred; Backes, Frank; Menzel, Thomas (Production Engineering, 1998)
LFT Import::2019-07-16 (1588)

Teilprojekt 4: Berücksichtigung funktionsrelevanter Gestaltabweichungen bei der Auslegung von Umformprozessen zur Herstellung von Stirnrädern mit Sonderverzahnung durch Fließpressen - Rohrmoser, Andreas; Hagenah, Hinnerk; Merklein, Marion (Abschlussbericht DFG-Forschungsgruppe FOR 2271, 2. Phase.Prozessorientiertes Toleranzmanagement mit virtuellen Absicherungsmethoden, 2023)

Temperature and stress development in the DMLS process - Niebling, Frank; Otto, Andreas; Geiger, Manfred (LANE 2004, Proceedings of the 4th International Conference on Laser Assisted Net Shape Engineering, 2004)
LFT Import::2019-08-05 (1105)

Temperature-based online quality control for laser brazing with high-power diode lasers - Grimm, A.; Schmidt, Michael; Hoffmann, Peter (Lasers in Manufacturing 2007 Proceedings of the Fourth International WLT-Conference on Lasers in Manufacturing Munich, Germany, June 18th-22nd, 2007)
LFT Import::2019-08-05 (1411)

Temporal and spatial detection of the onset of local necking and assessment of its growth behavior - Jaremenko, Christian; Affronti, Emanuela; Merklein, Marion; Maier, Andreas (Materials, 2020)
This study proposes a method for the temporal and spatial determination of the onset of local necking determined by means of a Nakajima test set-up for a DC04 deep drawing and a DP800 dual-phase steel, as well as an AA6014 aluminum alloy. Furthermore, the focus lies on the observation of the progress of the necking area and its transformation throughout the remainder of the forming process. The strain behavior is learned by a machine learning approach on the basis of the images when the process is close to material failure. These learned failure characteristics are transferred to new forming sequences, so that critical areas indicating material failure can be identified at an early stage, and consequently enable the determination of the beginning of necking and the analysis of the necking area. This improves understanding of the necking behavior and facilitates the determination of the evaluation area for strain paths. The growth behavior and traceability of the necking area is objectified by the proposed weakly supervised machine learning approach, thereby rendering a heuristic-based determination unnecessary. Furthermore, a simultaneous evaluation on image and pixel scale is provided that enables a distinct selection of the failure quantile of the probabilistic forming limit curve.
CRIS-Team Scopus Importer:2020-07-17
Keywords: Artificial intelligence; Classification; Deep learning; Forming limit curve; Machine learning; Pattern recognition; Segmentation; Sheet metal forming

Tensile testing of sheet metals at elevated temperatures with optical strain rate control - Naumann, David; Merklein, Marion (44th Conference of the International Deep Drawing Research Group (IDDRG 2025), 2025)
The manufacturing of sheet metal parts from lightweight alloys is often restricted due to limited formability of the applied materials at room temperature. To overcome this issue, thermally supported forming processes like hot forming are used. To map and predict the material behaviour in simulations, the materials have to be characterised at elevated temperatures. For the elasto-plastic behaviour, this typically is done by tensile tests. Thereby, dependent of the testing system, inhomogeneous temperature distributions are introduced to the sample unintentionally. This commonly known issue leads to an unintended increase of the strain rate during testing. Optical strain rate controlling (OSRC) is a new approach that enables the determination of the strain hardening behaviour of sheet materials at a constant true strain rate. Hence, in the scope of this contribution, the titanium alloy Ti-6Al-4V, is investigated at temperatures between 600 °C and 900 °C, at strain rates of up to 0.1 s-1. The tensile tests were carried out on a Gleeble 3500 GTC simulator together with an ARAMIS 3D DIC system for the in-situ strain measurement. The deviation of the strain rate evolution was improved up to fourfold by using the OSRC method in comparison to the conventional testing procedur
Keywords: tensile test Gleeble / DIC / strain rate

Test method for friction characterization of rivets - Wituschek, Simon; Kuball, Clara-Maria; Merklein, Marion; Lechner, Michael (Defect and Diffusion Forum, 2020)
Due to continuously increasing requirements on lightweight sheet metal constructions, new processes and technologies are necessary to face current and future challenges. A trend in lightweight construction is the multi-material mix with sheets of different geometric and mechanical properties. To manufacture these so-called composite structures, new joining technologies and methods are required. One possibility is the further development of the self-pierce riveting joining process. For the simulation and evaluation of new and adapted processes of self-pierce riveting, numerical models are used to investigate process parameters and constraints. Besides precise material models for the numerical simulation of this joining process, the identification of friction parameters between the individual sheets and rivet elements is necessary to achieve exact results. Thus, a method is necessary to identify the friction coefficients between rivet elements and sheets. Such a method is presented and evaluated in this work. Different process parameters like the relative speed are varied for the experimental investigations and an analysis of the respective influence on the resulting friction coefficients is conducted. For the use of the test set-up, coefficients of friction are determined for rivet elements “RIVSET® C 5.3x5.5” (Böllhoff GmbH) coated with Almac® in combination with two different sheet materials HCT590X+Z and EN-AW 6014.
CRIS-Team Scopus Importer:2020-12-04
Keywords: Friction; Joining; Self-piercing riveting

THE "A" Coatings - Merklein, Marion; Bouzakis, Konstantinos D.; Michailidis, Nikolaos; Denkena, Berend; Bobzin, Kirsten (Scientific.Net, 2020)
The book publishes selected papers from the 14th International Conference 2020 "THE A COATINGS" (19th - 20th November 2020, Nuremberg, Germany). The conference was focussed on coatings and research regarding coatings in different fields. Articles describe the results of research and development deposition process technologies, new coatings, surface properties, tribology, numerical simulation and modeling as well as the application of coatings for tools and product
Keywords: Coating Properties; Coatings; Laser Implantation; Laser Polishing; Physical Vapor Deposition; Solid Lubricant Coating; Surface Modification; Tool Surface; Tribological Performance; Wear Behaviour

The Application of Lasers in Micro Electronics Manufacturing - Fleckenstein, Marc; Schmidt, Michael; Eßer, Gerd (Chip Scale Review Magazine: Technical Proceedings and Presentations of the Chip Scale International (CSI) Europe 98, 1998)
LFT Import::2019-08-05 (1376)

The Coatings in Manufacturing Engineering - Merklein, Marion; Bach, Friedrich-Wilhelm; Bouzakis, Konstantinos D.; Denkena, Berend; Geiger, Manfred; Toenshoff, H. - K. (Trans Tech Publications, 2010)
Coating technology has made great strides during recent years. The properties of surface layers determine the function and quality of entire components. Thus, it is essential to obtain information concerning the development and functionality of the topmost layers. The beneficial effect of coating technology can be observed in many manufacturing fields, where it solves problems such as wear, corrosion, erosion, electrical contact, etc. Even decoration falls under this headin
Keywords: Aluminium Oxide; Bionic Layer; Coating; Cohesive Damage; Contact Angle (CA); Diamond-Like Carbon (DLC); Finite Element Analysis (FEA); Friction; Hot Stamping; Mechanical Property; Optically Non-Cooperative Surface; Plasma Nitriding; Precision Glass Molding; PtIr; PVD Film; Simulation; Thermal Spraying; Tribology; Ultra-Precision Machining; Wear

The correlation coefficient method: from the beginning to the development - Merklein, Marion; Affronti, Emanuela; Kuppert, Andreas; Maier, Anne-Kathrin; Lechner, Michael (Workshop Time-dependent Methods for the Evaluation of FLC, 2014)
LFT Import::2019-08-05 (2053)

The ESAFORM benchmark 2023: interlaboratory comparison benchmark for the characterization of microstructural grain growth and dynamic recrystallization kinetics of a single-phase Ni-base superalloy - Agirre, Julen; Bernal, Daniel; Flipon, Baptiste; Bernacki, Marc; Brüggemann, Holger; Bailly, David; Merklein, Marion; Hagenah, Hinnerk; Risse, Jan Henning; Madej, Łukasz; Muszka, Krzysztof; Cichocki, Kamil; et al. (International Journal of Material Forming, 2025)
This paper presents an extensive benchmark study conducted across eight European research centres, focusing on the high-temperature testing of the Alloy 625 nickel-based superalloy to evaluate its flow behaviour and microstructural evolution, including grain growth (GG) and dynamic recrystallization (DRX). Uniaxial compression tests were performed at 1050 °C and three strain rates (0.1 s⁻1, 1 s⁻1, and 10 s⁻1) using six testing facilities categorised into three types: two conventional thermomechanical machines equipped with electrical resistance furnaces, two deformation dilatometers with induction heating, and two Gleeble machines with Joule heating. Flow curves were compared, and EBSD analysis was conducted to examine DRX. Virtual twins of tests were developed to estimate the thermomechanical history at the centre of the samples, where microstructural observations were conducted. The study methodically discussed the variability in thermomechanical behaviour and DRX results. Additionally, GG was investigated through heat treatments at 1150ºC for various hold times, using the three heating methods mentioned. Significant effects of the heating methods on GG were identified. In-situ synchrotron analysis at PETRA III DESY provided deeper insights into microstructural evolution. Considering the extensive findings of this research, this paper aims to establish guidelines and define best practices for high-temperature testing to characterise the thermomechanical behaviour and microstructural evolution of materials, while providing insights for advancing experimental mechanics and optimising constitutive model development.
Created from Fastlane, Scopus look-up
Keywords: Benchmark; High temperature testing; Uniaxial compression; Microstructural evolution; Grain growth; Dynamic recrystallization; EBSD analysis; Virtual twins; In-situ testing

The influence of the annealing process in the fabrication of helical needles for the suture in deep wound cavities - Plettke, Raoul; Vipavc, Daniel; Grüner, Martin; Hagenah, Hinnerk; Merklein, Marion (International Journal of Computer Integrated Manufacturing, 2014)
The standard procedure of a surgical suture can be very difficult to perform in deep-wound cavities because the available space is not enough to perform the complicated movements required for the knot or to handle the needle. To improve this situation a new kind of hollow, helical needle was developed and filed for patent. To ensure the manufacturability of this kind of needle, a prototype and a prototypical tool were designed and tested. As a prototypical basis, commercially available cannulas were selected. Coil winding was used as a forming process to bring the cannula into the helical form. The material properties of the surgical steel and the work hardening that the semi-finished products underwent lead to challenges for the forming process. The limitations of springback and low formability reduce the possible radius of the helix. Therefore, a soft annealing of the cannula was investigated. However, in surgical needles, stiffness is of great importance. Since hardening by quenching is not possible, annealing parameters were chosen to retain the necessary stiffness. Based on the data obtained from tests of annealing parameters, four final geometries of helical needles were designed and first prototypes were manufactured. © 2013 Taylor & Francis.
LFT Import::2019-07-29 (1901)
Keywords: annealing; case study; deep wound; helical needle; suture; winding

The Mechanisms of Laser Forming - Geiger, Manfred; Vollertsen, Frank (CIRP Annals - Manufacturing Technology, 1993)
Laser forming is a complex dynamic forming process. Its basic feature is the forming by thermal stresses, induced by irradiation of a laser beam. A two-layer model for laser bending is proposed, which is capable to describe the process in spite of many restrictions which have to be made. It is shown that the coefficient of thermal expansion is one of the most significant parameters for the process. The model shows the right dependence on the sheet thickness and the right order of magnitude for the bend angle which can be obtained in one step of the laser bending process. Possible extentions of the model are discussed, using experimental results which had shown that the neutral line lies at a relative thickness z/s0 = 0.65. © 1993 CIRP.
LFT Import::2019-07-15 (414)
Keywords: forming; laser beam application; simulation

Thermisches ätzen zur Bestimmung der Austenitkorngröße in sehr kohlenstoffarmen Stählen - Pöhl, Christopher; Gamsjäger, E.; Leitner, H.; Clemens, H. (Praktische Metallographie, 2009)
LFT Import::2019-07-29 (1570)

Thermisch unterstützte Umformung von Aluminiumblechen - Kahrimanidis, Alexander (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2016)
The formability of aluminum alloys can be extended by using tailor heat treated blanks (THTB). This book gives an introduction to the basics of producing complex part geometries with THTB and demonstrates how the technology can be used in an industrial application by manufacturing an outer skin part of a passenger car. Thereby the book presents a holistic approach for the production and processing of THTB that can be transferred to any other part geometr

Thermo-mechanical Laser Process Design: Virtual Reality in Use - Komlodi, Attila; Niebling, Frank; Merklein, Marion; Otto, Andreas (EuroPAM, Proceedings of the 13th European Conference and Exhibition on Digital Simulation for Virtual Prototyping, Virtual Manufacturing and Virtual Environment, 16-17. Oktober, 2003)
LFT Import::2019-08-05 (971)

Thermo-Mechanical Properties of Tailor Welded Blanks in Hot Sheet Metal Forming Processes - Lamprecht, K.; Deinzer, G.; Stich, A.; Lechler, Jürgen; Stöhr, Thomas; Merklein, Marion (Proc. 50th Conference of IDDRG 2010, 2010)
LFT Import::2019-08-05 (226)

Thermo-mechanical sheet metal forming of aero engine components in Ti-6Al-4V–PART 1: Material characterisation - Odenberger, E.-L.; Hertzman, J.; Thilderkvist, P.; Merklein, Marion; Kuppert, Andreas; Stöhr, Thomas; Lechler, Jürgen; Oldenburg, M. (International Journal of Material Forming, 2012)
LFT Import::2019-07-29 (1838)

The use of dry film lubricants in aluminium sheet metal forming - Meiler, M.; Pfestorf, Markus; Geiger, Manfred; Merklein, Marion (Wear, 2003)
LFT Import::2019-07-16 (1005)
Keywords: Aluminum; Friction; Textures; Tribology

The use of kinematic chains and construction catalogues for an advanced design of complex actuator geometries in micro adjustment - Wurm, Thomas; Menzel, Thomas; Müller, Burkhard; Hagenah, Hinnerk; Geiger, Manfred (Proceedings: International CIRP Design Seminar: Design in the New Economy; Design Theory, Methodology and its Intergration with the Computational Tools to support Teams of Competence, 2001)
LFT Import::2019-08-05 (824)

Three Dimensional Characterization of Surfaces for Sheet Metal Forming - Pfestorf, Markus; Engel, Ulf; Geiger, Manfred (Wear, 1998)
In metal-forming processes, the load at the interface between workpiece and die is transmitted by three different kinds of bearing ratios. These are the real contact area, which is represented by the solid contact, and the static and dynamic lubricant pockets. As the real contact area is already well known from other researchers, the static and dynamic lubricant pockets are newly defined bearing ratios that characterize the contact mechanisms in mixed lubrication. To determine them with respect to the topography, three-dimensional surface parameters have to be defined. These are the material area ratio, as well as the open and closed void area ratio. As it is shown in the paper, the maximum of the closed void area ratio and the closed void volume seem to be distinctive features for characterizing the tribological properties of the surface, even if there are only slight variations in the surface topography. In order to determine these characteristic parameters, the surface is mapped three-dimensionally by an optical measuring device. Based on the measured surface data, the area ratios can be calculated by the program SAM (surface analysis module) which will also be presented in the paper. © 1998 Elsevier Science S.A. All rights reserved.
LFT Import::2019-07-16 (1616)
Keywords: 3D surface parameters; Sheet metal forming; Tribology

Three Dimensional CO2-Laser Material Processing with Gantry Machine Systems - Hoffmann, Peter; Biermann, Stefan; Geiger, Manfred; Nuss, Rudolf (Tagungsband Int. Congress on Optical Science & Engineering, 1990)
LFT Import::2019-08-05 (733)

Three kinds of case-based learning in sheet metal manufacturing - Cser, L; Geiger, Manfred; Greska, Wolfgang (Computers in Industry, 1991)
The paper outlines three applications of case-based learning in sheet metal manufacturing by utilization of artificial intelligence, each based on different concepts. One topic is the synthesis with feature processing for the process outline on a CNC bending machine. Statistics on fail and success influence weights of rules in an expert system. Another example is the classification of sheet metal parts. Real objects and their components are represented by a frame like data structure, which is embedded in a semantic network. Grouping of work pieces is done by a decision method of Bayes. This method is also used for part diagnosis to avoid possible defects of tools and machines. © 1991.
LFT Import::2019-07-15 (232)
Keywords: Classification; Computer aided planning; Failure; Features; Forming; Knowledge based systems

Time dependent determination of forming limit diagrams - Merklein, Marion; Kuppert, Andreas; Geiger, Manfred (CIRP Annals - Manufacturing Technology, 2010)
LFT Import::2019-07-29 (297)
Keywords: Failure criterion; Forming; Sheet metal

Time dependent FLC determination - Comparison of different algorithms to detect the onset of unstable necking before fracture - Hotz, Walter; Merklein, Marion; Kuppert, Andreas; Friebe, Harald; Klein, Markus (Key Engineering Materials, 2013)
The ISO standard 12004-2:2008E for the determination of forming limit curves based on the section method was approved in 2008. About 4 years of measuring experience in different laboratories has shown advantages and weaknesses of the standard and is leading to some minor changes in the specification. In the years from the development of this standard until today a further technical development of the optical measuring devices occurred, so that it is now possible to determine forming limit curves using the time history of the test. This procedure of determination is referred to a time dependent technique and could be the basis of the ISO 12004 part 2 proposal worked out by the work group "Erweiterung FLC ISO 12004" of the German group of the IDDRG. This publication recapitulates existing work which was carried out from the IDDRG work group regarding the determination of forming limit curves for sheet metal materials. On one hand known issues with the current section based approach are discussed and on the other hand it deals with a comparison of different algorithms to determine the FLC from the time history of the Nakajima test using strategies to identify the instant of onset of instable necking. The different time dependent algorithms [1] utilised are automatically selecting the area where necking is leading to fracture and then analyze the time history of such points using the first or the second time derivative of the true major strain, or of the true thinning strain using methods like: correlation coefficient (modified method based on [2]), gliding correlation coefficient, linear best fit (modified method based on [3]) and gliding difference of mean to median. The resulting experimental FLC points are compared with the results from the section technique described in ISO 12004 part 2 and with the maximum strain values measured in each test. Further a large number of forming limit curves were determined and used for a comparison of these different methods to define the most promising time dependent algorithm, which was selected as a suggestion for the working group defining the new proposed ISO standard 12004 part 2. © (2013) Trans Tech Publications.
LFT Import::2019-07-29 (1927)
Keywords: Forming limit curve (FLC); Material characterization; Time depending evaluation methods

Time efficient Micro-Adjustment Based on a New Type of Laser-Operated Actuators - Dirscherl, Manfred; Eßer, Gerd; Geiger, Manfred (Proceedings Sensor 2003, Vol I, 2003)
LFT Import::2019-08-05 (981)

Titanium metal sheet structures of various wall thicknesses with additional functional elements prepared by selective electron beam melting in a powder bed - Juechter, V.; Schaub, Adam; Merklein, Marion; Singer R., F. (5th International Conference on Additive Technologies - iCAT2014, 2014)
LFT Import::2019-08-05 (2051)

Tool design for cold forging of high nitrogen steels - Noneder, Johannes; Engel, Ulf; Merklein, Marion (Proceedings of the 12th International Cold Forging Congress, 2011)
LFT Import::2019-08-05 (1741)

Tool development based on modelling and simulation of hot sheet metal forming of Ti-6Al-4V titanium alloy - Odenberger, E. -L.; Oldenburg, M.; Thilderkvist, P.; Stöhr, Thomas; Lechler, Jürgen; Merklein, Marion (Journal of Materials Processing Technology, 2011)
In the aero engine industry alternative manufacturing processes for load carrying aero engine structures imply fabrication. The concept of fabrication involves simple forgings, sheet metals and small ingots of e.g. titanium alloys which are welded together and heat treated. In the concept phase of the product development process, accurate evaluations of candidate manufacturing processes with short lead times are crucial. In the design of sheet metal forming processes, the manual die try out of deep drawing tools is traditionally a time consuming, expensive and inexact process. The present work investigates the possibility to design hot forming tools, with acceptable accuracy at short lead times and with minimal need for the costly die try out, using finite element (FE) analyses of hot sheet metal forming in the titanium alloy Ti-6Al-4V. A rather straightforward and inexpensive approach of material modelling and methods for material characterisation are chosen, suitable for early evaluations in the concept phase. Numerical predictions of punch force, draw-in and shape deviation are compared with data from separate forming experiments performed at moderately elevated temperatures. The computed responses show promising agreement with experimental measurements and the predicted shape deviation is within the sheet thickness when applying an anisotropic yield criterion. Solutions for the hot forming tool concept regarding heating and regulation, insulation, blank holding and tool material selection are evaluated within the present work. © 2011 Elsevier B.V. All rights reserved.
LFT Import::2019-07-29 (1690)
Keywords: FEM simulation; Hot forming test; Hot sheet metal forming; Ti-6Al-4V; Titanium alloys; Validation

Tooling Solutions for Challenges in Cold Forging - Engel, Ulf; Groenbaek, J.; Hinsel, Christian; Kroiss, Thomas; Meidert, M.; Neher, R.; Räuchle, F.; Schrader, Tobias (UTF-Science, 2011)
LFT Import::2019-07-29 (1770)

Tool Life Enhancement on Cold Forging by Locally Optimized Surfaces - Wagner, Kay; Völkl, Ralf; Engel, Ulf (Journal of Materials Processing Technology, 2007)
LFT Import::2019-07-16 (1464)

Tool Life Improvement by Surface Laser Texturing - Geiger, Manfred; Popp, Uwe; Engel, Ulf (THE Coatings, Proceedings of the 4th International Conference, 2004)
LFT Import::2019-08-05 (1042)

Tool life in cold forging - Engel, Ulf; Falk, Bernd (ICIT’99 Conference Proceedings (Int.Conf.on Industrial Tools, April 1999 Maribor, Slov) Vol. I, 1999)
None
LFT Import::2019-08-05 (1993)

Tool Life & Tool Quality in Bulk Metal Forming - Lange, K.; Kals, J.A.G.; Geiger, Manfred; Cser, Laszlo (Annals of the CIRP, 1992)
LFT Import::2019-08-07 (485)

Tool Load Sensitivity against Multidimensional Process Influences in Microblanking of Thin Metal Foils with Silicon Punches - Hildering, Sven; Michalski, Markus; Engel, Ulf; Merklein, Marion (Journal of Manufacturing Science and Engineering, 2016)
LFT Import::2019-07-29 (2169)

Tool Path Optimization for 2D Laser Cutting - Geiger, Manfred; Kollera, Harald (Production Engineering - Annals of the WGP, 1994)
LFT Import::2019-08-05 (593)

Tool Planning for Complex Bending Parts - Geiger, Manfred; Franke, Volker (Production Engineering, 1995)
LFT Import::2019-07-15 (539)

Tool Sided Surface Modifications in the Industrial Environment - Wild, Thomas; Merklein, Marion (Lecture Notes in Production Engineering (LNPE), 2020)
In order to meet the increasing requirements on modern production, the innovative process class of sheet-bulk metal forming has proved to be suitable. Particularly lightweight construction and functional integration lead to complex shaped functional elements. In addition to this, the widespread use of high-strength materials also results in challenges in the production of such components by forming. This leads to demanding forming processes, in which the die filling is often insufficient due to unintended material flow. In this respect, tailored surfaces offer one possibility of controlling the material flow and thus increasing component quality. This concept refers to the local adaptation of the tribological system during the forming of the components. Within this research project it is the objective to transfer the process knowledge that has been generated in the Transregional Collaborative Research Centre 73 (TCRC73) to the industrial environment. This involves investigating the impact of the requirements and influences of mass production on the efficacy and service life of the tailored surface. For this purpose, based on a finely ground reference surface, the effects of abrasive blasting and laser beam polishing as surface modifications of tool steels are investigated in a laboratory and industrial scale. Emphasis is placed on the formation of the modified surfaces, the effects on the tribological operational behaviour and the impact on the fatigue behaviour of tool steels.<br

Tool System for Ultrasonic-Assisted Forming and Material Characterisation with 15 kHz Oscillation Frequency - Michalski, Markus; Leicht, Uwe; Engler, S.; Merklein, Marion (Applied Mechanics and Materials, 2015)
LFT Import::2019-07-29 (2102)

Towards a better understanding of laser beam melt ablation using methods of statical analysis - Cser, Adrienn Orsolya; Donner, R.; Schwarz, U.; Otto, Andreas; Geiger, Manfred; Feudel, U. (Proceedings of the 3rd CIRP International Seminar on Intelligent Computation in Manufacturing Engineering (ICME 2002), 2002)
LFT Import::2019-08-05 (1672)

Towards an holistic account on residual stresses in full-forward extruded rods: Experiment, modeling and simulation of forming and operation phases - Floros, Dimosthenis; Jobst, Andreas; Kergaßner, Andreas; Merklein, Marion; Steinmann, Paul (Archive of Applied Mechanics, 2021)
An holistic view is attempted towards prediction of the effect of residual stresses induced by full-forward extrusion on fatigue life of workpieces during operation. To study the effect of constitutive model on the accuracy of forming simulations, a combined nonlinear isotropic/kinematic hardening model as well as the isotropic hardening part of the same model are calibrated based on five compression-tension-compression uniaxial stress experiments. A full-forward extrusion finite element model is developed adapting both the aforementioned hardening plasticity models and the predicted residual stress states at the surface of the workpiece are compared against that of a corresponding forming experiment. Results show residual stress predictions of remarkable accuracy by the FE-models with the isotropic hardening model. The effect of residual stresses on fatigue life of the workpiece is qualitatively studied by uncoupled multiscale simulations featuring gradient crystal plasticity at the microscale. While the effective (homogenized) macroscale response indicates elastic response during a macroscopically cyclic loading, plasticity accompanying reduction of residual stresses is still present at the microscale within, e.g. grain boundaries.
CRIS-Team Scopus Importer:2021-03-19
Keywords: Cold forming; FE-simulations; Kinematic hardening; Multiscale modeling; Residual stress

Towards Biomechanical Digital Human Modeling of Elderly People for Simulations in Virtual Product Development - Miehling, Jörg; Geißler, Bastian; Wartzack, Sandro (Proceedings of the Human Factors and Ergonomics Society 2013 International Annual Meeting, 2013)
This contribution illustrates a methodology to customize biomechanical digital human models to resemble people of different age and ability groups for the use in simulations to support user-centered design. Especially the conception of man models of elderly people holds potential for analyzing and optimizing products to yield more universal designs, due to the high heterogeneity of needs, wants and capabilities in this specific age group. The present approach considers age-related performance restrictions, but is also extendable to disease-related limitations. The conception process itself includes the scaling of anthropometry, muscle forces, range of motion as well as motion speed based on data from literature or manual measurements. The parameters are either selected by percentiles or the specific values itself.
UnivIS-Import:2015-04-16:Pub.2013.tech.FT.FT-KLMEFK.toward

Towards Hot Crack Free Welding of Aluminium alloys Using FEM Simulations - Geiger, Manfred; Komlodi, Attila; Otto, Andreas (Production Engineering - Annals of the WGP (2004), 2004)
LFT Import::2019-08-05 (1092)

Towards multi parameter control for laser beam welding - Hohenstein, Ralph; Agakov, Felix (Idee-Vision-Innovation, Festschrift anläßlich des 60. Geburtstages von Professor Manfred Geiger, 2001)
LFT Import::2019-07-15 (969)

Towards optimized lubrication by micro texturing of tool surfaces - Neudecker, Thomas; Popp, Uwe; Engel, Ulf; Geiger, Manfred (Advanced Technology of Plasticity 1999, Proc. of the 6th Int. Conf. on Technology of Plasticity, Vol. 1, 1999)
None
LFT Import::2019-08-05 (1998)

Towards virtual deformation dilatometry for the design of hot stamping process - Bambach, Markus; Buhl, Johannes; Hart-Rawung, T.; Lechner, Michael; Merklein, Marion (Procedia Engineering, 2017)
Hot stamping is a well-established process for the production of structural automotive parts with an excellent strength-to-weight ratio. The complexity of the thermo-mechanical history in hot stamping requires a precise virtual design of hot stamping processes. The thermal and mechanical characteristics of the most common press hardening steel 22MnB5 were investigated comprehensively and are well represented by numerical models. For new steel compositions and parts involving tailored tempering, numerous experiments, e.g., on a deformation dilatometer or thermo-mechanical simulator are needed to characterise the microstructure evolution and the resulting properties. If appropriate material models were available, new steel compositions and thermo-mechanical histories could be partly explored virtually by simulated deformation dilatometer tests. This paper presents a comparison of experimental and virtual deformation dilatometer tests for the hot stamping steel 22MnB5. The virtual dilatometer is implemented as finite element model in the software LS-Dyna based on the material model∗MAT248. With this model, virtual and real dilatometer curves correspond well only for conditions of full martensitic hardening, while pre-strains cause larger differences between model and experiments. When the most sensitive model parameters are formulated as a function of pre-strain, all experimental dilatometer curves can be reproduced by the model. Such a data-driven extension of the model seems to be effective for creating a virtual dilatometer model of high accuracy.
CRIS-Team Scopus Importer:2023-03-29
Keywords: Autenite decomposition model; Dilatometry test; Hot Stamping

Towars Improved Tool Life in Cold Forging by Micro Texturing of Tool Surfaces - Popp, Uwe; Neudecker, Thomas; Engel, Ulf (Proceedings of the 4th International Conference on Industrial Tools (ICIT 2003), 2003)
LFT Import::2019-08-05 (934)

Tranciatura ad alta precisione di fogli di rame mediante punzoni in silicio monocristallino rivestiti e non - Hildering, Sven; Becsi, L.; Merklein, Marion; Mescheder, U. (Lamiera, 2012)
LFT Import::2019-07-29 (1808)

Transfer of Contact Conditions for Failure Analysis of Metal Forming Tools - Sobis, Tomasz; Engel, Ulf; Geiger, Manfred (Numerical Methods in Industrial Forming Processes - NUMIFORM 92, Rotterdam : Balkema, 1992)
LFT Import::2019-08-05 (489)

Transformation kinetics of the hot stamping steel 22MnB5 in dependency of the applied deformation on the austenitic microstructure - Merklein, Marion; Svec, Thomas (Proc. 50th Conference of IDDRG 2010, 2010)
LFT Import::2019-08-05 (277)

Trends in der Aluminiumumformung - Merklein, Marion; Lechner, Michael; Kuppert, Andreas (Tagungsband zum Cluster-Forum Innovationen in der Aluminium-Umformtechnik, 2012)
LFT Import::2019-07-29 (1943)

Triangulation based digitizing of tooling and sheet metal part surfaces? measuring technique, analysis of deviation to CAD and remarks on use of 3D-coordinate fields for the finite element analysis - Hecht, Joachim; Lamprecht, Klaus; Merklein, Marion; Galanulis, K.; Steinbeck, J. (Proceedings of the 12th International Conference on Sheet Metal (SheMet), 01.-04.04., Palermo, Italy, 2007)
The dynamic development of highly accurate optical measuring machines within the last years pushed the introduction of digitizing techniques to many applications in the fields of quality control, reverse engineering and rapid prototyping. By projecting fringe patterns onto the object's surface and recording pictures of the curvature dependant deformation of the pattern, 3D coordinates for each camera pixel are calculated on the basis of the principle of triangulation. The generation of a polygon mesh can be used for the analysis of the deviation of a die or a formed part to the initial CAD data, i.e. by means of full field or section based comparison. This paper presents the application of the above mentioned techniques on a double sheet hydroforming process. The gathered 3D data of the clam-shell part as well as of the tooling dies served for the calculation of the deviation to the respective reference geometry. With respect to the utilization of digitized tooling data within the finite element analysis, further investigations were performed on the impact of data reduction strategies. Aiming on the minimization of the necessary number of elements, representing the tooling surface in a discrete state, and on the request for a sufficient degree of accuracy, these strategies have to be considered of high priority.
LFT Import::2019-08-05 (1383)
Keywords: FE simulation; Sheet metal forming and tooling; Triangulation based digitizing

Tribiological Properties of Dry Film Lubricants in Aluminium Sheet Metal Forming. - Meiler, M.; Pfestorf, Markus; Merklein, Marion; Geiger, Manfred (Processing of the 2nd International conference on Tribology in Manufacturing Processes, Nyborg, Denmark, June 15-18 2004, 2004)
LFT Import::2019-08-05 (1057)

Tribological and thermal behavior of laser implanted tool surfaces for hot stamping AlSi coated 22MnB5 sheets - Schirdewahn, Stephan; Spranger, Felix; Hilgenberg, Kai; Merklein, Marion (Defect and Diffusion Forum, 2022)
In the automotive industry, the development of electrically powered vehicles has become a major forward-looking topic. For improving the range and thus the efficiency of electric cars, lightweight construction has gained even more importance. In this regard, hot stamping has been established as a suitable and resource efficient process to manufacture high-strength and lightweight body-in-white components. This method combines hot forming and quenching of boron-manganese steel 22MnB5 in a single process step. As a result, complex structures with thin sheet thicknesses and high ultimate tensile strength up to 1500 MPa are generated. However, the use of lubricants is not possible at elevated temperatures, which subsequently leads to high thermo-mechanical tool stresses. As a side effect, high friction and severe wear occur during the forming process, which affect the resulting part quality and maximum tool life. Therefore, the aim of this study is to improve the tribological performance of hot stamping tools by using a laser implantation process. This technique is based on manufacturing highly wear resistant, separated and elevated structures in micrometer range by embedding hard ceramic particles into the tool material via pulsed laser radiation. As a result, highly stressed areas on the tool surface can be modified locally, which in turn influence the tribological and thermal behavior during the forming process. In this regard, laser implanted and conventionally tool surfaces were investigated under hot stamping conditions. A modified pin-on-disk test was used to analyze the friction coefficient and occuring wear mechanisms. Furthermore, quenching tests as well as hardness measurements were carried out to gain in-depth knowledge about the cooling behavior of the modified tool surfaces and its impact to the resulting mechanical part properties.<br
Keywords: Hot stamping; Laser implantation; Surface structuring; Tribology

Tribological and thermal investigation of modified hot stamping tools - Neubauer, Franziska; Merklein, Marion (Tribology in Industry, 2019)
Direct hot stamping is an established manufacturing process to produce safety-relevant car body components, while t-he hot blank is formed and quenched simultaneously in a water cooled press. In order to protect the semi-finished parts against oxidation the surfaces are coated with aluminum silicon. As a side effect this coating system leads to adhesive wear on the tool surface, which reduces the tool life. Due to the high temperatures it is not possible to use lubricants as wear protection. For this reason a suitable surface modification for hot stamping tools is required to increase the wear resistance. In the scope of this study the tribological behavior of different modificatiosn is investigated. The main purpose of these wear protective layers is to decrease the adhesive wear on the tool surface. The wear characterization is carried out with a modified pin-on-disc test. During the experiments the pin is guided over the blank with a robot system. In addition, the contact area is cooled after each wear track to simulate the thermal alternating stresses of the hot stamping process. For the evaluation of the wear behavior a new developed analysis method is used, which enables the calculation of the adhesive and abrasive wear volume.
CRIS-Team Scopus Importer:2019-06-21
Keywords: Alloying; Coatings; Hot stamping; Wear

Tribological aspects in manufacturing processes of microstructured components and their tribological behavior in operation - Schrader, Tobias; Weschta, Martin; Merklein, Marion; Tremmel, Stephan; Engel, Ulf; Wartzack, Sandro (Proc. 6th International Conference on Tribology in Manufacturing Processes and Joining by Plastic Deformation, 2014)
An ever increasing mobility and a shortage of resources lead to restrictive politically driven limits for fuel consumption as well as an increasing demand of customers for efficient vehicles. Though electrification of cars proceeds, combustion engines will play an important role for conventional and hybrid concepts within next decades. Thus, for a contribution to increasing energy efficiency of vehicles it is vital to trace sources of friction losses and to identify possibilities for friction reduction in combustion engines. Therefore, the follower as a main contributor to friction losses in valve trains was chosen as a demonstrator for friction reduction effects by microstructured components. However, the realization of theoretically advantageous microstructures with filigree geometries is challenging for manufacturing technologies. The present study focuses on the elaboration of a technological basis for a repeatable production of components with microstructured surfaces by a combined cup backward extrusion micro coining process, coping with the demands of large-lot production. For realization of a high accuracy the influence of friction on geometry of microstructured components was investigated. In addition, running-in of components is decisive for final geometry and tribological behavior of microstructured surfaces and hence considered as well.
Keywords: Accuracy; Microstructures; Tribology

Tribological Behavior of Carbon Based Coatings Adapted to Lubricant-Free Forming Conditions - Tenner, Jennifer; Zhao, Rong; Tremmel, Stephan; Häfner, Tom; Schmidt, Michael; Merklein, Marion (International Journal of Precision Engineering and Manufacturing - Green Technology, 2018)
In conventional deep drawing lubricants are applied to achieve low friction and wear. However, most lubricants contain environmental harmful ingredients. Global trends like sustainability and efficient resource usage motivate the development of lubricant-free deep drawing. However, dry contact conditions lead to intensive interaction between tool and workpiece especially for aluminum alloys with high adhesion tendency towards tool steel. First investigations revealed promising results for diamond like carbon (DLC) coated tools in lubricant-free tests. Therefore, in this study the lubricant-free friction and wear behavior of DLC coatings is investigated in strip drawing tests. To ensure industrial-like conditions commonly used deep drawing steel with zinc coating and an aluminum alloy were selected as sheet material. The properties of DLC coatings were modified at different scales to attain tailored tribological conditions. A laser based heat treatment achieved an increase of sp2 hybridization and thus leads to increased friction. Different mechanical pre- and post-treatment strategies like polishing and brushing proved that a smooth tool surface is beneficial for the tribological conditions in dry contacts. With laser generated structures a modification of friction was realized with varying degree of coverage for DC04. In contact with AA5182 the application of structures is limited due to adhesion.
CRIS-Team Scopus Importer:2022-06-05
Keywords: Carbon based coatings; Dry deep drawing; Surface modification; Tribology

Tribological Behavior of Different Tool Steels and Surface Properties under Hot Stamping Conditions - Schwingenschlögl, Patrik; Tenner, Jennifer; Merklein, Marion (Key Engineering Material, 767, 2018)
LFT Import::2019-08-05 (2313)
Keywords: 22MnB5; Friction; Hot stamping; Tool steel; Wear

Tribological Behavior of High-Strength Aluminum Alloys in Combination with Dry Lubricants at High Forming Temperatures - Rigas, Nikolaos; Junker, Friedhelm; Berendt, Erik; Merklein, Marion (Defect and Diffusion Forum, 2022)
High-strength aluminum alloys provide great potential for weight reduction in vehicle and aircraft production. Nevertheless, forming of these materials is limited at room temperature. Thermally supported forming operations such as hot forming and quenching (HFQ®) allow forming of components without failure and reduced springback. Currently, the adhesive wear and high friction limit the use of HFQ®-operations for high-strength aluminum alloys. Out of this reason, the present paper describes the tribological performance of new developed dry lubricants at elevated temperatures for the alloy AA7075. For this purpose, strip drawing tests were carried out in a modified open tribological system at temperatures between 20 °C and 400 °C. Additionally, the melting behavior of these lubricants, as well as the variation of the lubricant thickness, were investigated. The results show a reduction of the coefficient of friction at elevated temperatures.
Keywords: Tribology; Hot stamping; Lubrication; High-strength aluminum

Tribological behavior of Zn coated 22MnB5 in hot stamping - Schwingenschlögl, Patrik; Tenner, Jennifer; Andreas, Kolja; Merklein, Marion (Steels in Cars and Trucks, 2017)
LFT Import::2019-08-05 (2235)

Tribological challenges in press hardening - Schwingenschlögl, Patrik; Merklein, Marion (Stahl und Eisen, 2019)
Hot stamping has established as a common technology for manufacturing safety-relevant components in modern vehicle bodies. By applying thin sheet thicknesses, using hot stamped parts offers the chance of improving crash performance while towering the mileage. The most commonly used material for hot stamped components is the high-strength-steel 22MnB5. In order to avoid the formation of oxide scale during the heat treatment and the subsequent forming process, an AISi coating is applied to the boron-manganese-steel. Due to the forming temperatures between 600 °C and 850 °C, no suitable lubricants have been found yet. Thus, high friction and severe wear occur during the forming. This has an impact on the resulting part quality as well as the tool lifetime. As a consequence, future measures that reduce the tribological loads have to be found in order to improve the robustness and the efficiency of industrial hot stamping applications. Within this study, friction and wear are characterized for different workpiece and tool temperatures, relative velocities and contact pressures. Based on the experimental results, suggestions regarding the process design of hot stamping applications will be given.
CRIS-Team Scopus Importer:2021-04-20

Tribological characterization of PVD-coatings - Schrader, Tobias; Engel, Ulf; Merklein, Marion (Key Engineering Materials, 2010)
LFT Import::2019-07-29 (1015)
Keywords: Coating; Cold forging; Wear

Tribological Conditions in Sheet-Bulk Metal Forming - Vierzigmann, Ulrich; Merklein, Marion; Engel, Ulf (2nd International Conference of Engineering Against Fracture, 2011)
LFT Import::2019-08-05 (1739)

Tribological conditions within hot stamping process - Merklein, Marion; Wieland, Michael; Zöller, Fabian (Proc. of 7th Forming Technology Forum - Warm and Hot Forming, 2014)
LFT Import::2019-08-05 (2043)

Tribological Investigations on Coated Steel Sheets using the Dry Film Lubricant Drylube E1 - Tolazzi, Massimo; Merklein, Marion; Meiler, M. (Sheet Metal 2005, Proceedings of the 11th International Conference on Sheet Metal; Advanced Materials Research, 2005)
Tribological aspects strongly influence the deep drawing behaviour of sheet metal, being responsible for both the punch force and the material draw-in from the flange. Recent developments in lubrication technology have shown that dry film lubricants can be a good alternative to conventional fluid lubricants in case of aluminium sheets. Their main advantages are the homogeneous distribution on the blank surface, the good adhesion to the surface and the possibility of applying it already in the rolling mill. In order to introduce this technology in series production also for steel sheets more knowledge concerning the influence of the lubricant amount on the drawing forces is needed. A further important aspect to be considered is the surface quality of the steel grades and its interactions with the dry lubricant. In this paper four steel grades with different mechanical and/or surface properties are considered. After a microscopical and topographical investigation of the surface the materials were tested in a cup drawing test after applying two different amounts of the dry film lubricant Drylube El. Further process parameters which were varied are the blank holder force FN and the drawing ration β. In this way, information about the influence of the lubricant amount on both the drawing force and on the maximum blank holder force Fz could be obtained for three different values of β. The experimental results have shown how a strong decrease of the lubricant amount (from 1.0 down to 0.5 g/m2) causes, at a given drawing ratio, only a small increase in the maximum drawing force as well as a small increase in the maximum blank holder force.
LFT Import::2019-08-05 (1129)
Keywords: Dry film lubricant; Sheet metal; Tribotogy

Tribological measures for controlling material flow in sheet-bulk metal forming - Löffler, Maria; Andreas, Kolja; Engel, Ulf; Schulte, Robert Karl; Gröbel, Daniel; Krebs, Eugen; Freiburg, Dennis; Biermann, Dirk; Stangier, Dominic; Tillmann, Wolfgang; Weikert, Tim; Wartzack, Sandro; et al. (Production Engineering, 2016)
Sheet-bulk metal forming (SBMF) is characterized by successive and/or simultaneous occurrence of quite different load conditions regarding stress and strain states. These conditions significantly influence the material flow and thus the geometrical accuracy of the components. To improve the product quality a control of the material flow is required. An appropriate approach is given by locally adapted tribological conditions due to surface modifications of tool and workpiece, so-called tailored surfaces. Within the present study different methods to adapt the surfaces are presented and investigated with respect to their tribological effectiveness in SBMF. In a first step, requirements regarding necessary adaptions of the friction values for two SBMF processes are numerically defined. Based on the requirements different tailored surfaces are presented and analyzed regarding their tribological influence. Finally, the potential of surface modifications to improve SBMF processes is shown.
Keywords: Tribology; Surface modification; Sheet-bulk metal forming

Tribological performance of localized dispersed X38CrMoV5-3 surfaces for hot stamping of Al-Si coated 22MnB5 sheets - Schirdewahn, Stephan; Spranger, Felix; Hilgenberg, Kai; Merklein, Marion (Hot Sheet Metal Forming of High-Performance Steel CHS², 2019)
Over the last years, the weight of modern car bodies has risen significantly due to the increasing customers’ demand for comfort and safety equipment. However, this ongoing trend leads to an increasing fuel consumption and thus to higher carbon dioxide emissions. In order to counteract these problems, hot stamping has been established in the automotive industry as a key technology for lightweight construction, regarding the manufacturing of safety-relevant car body components. Hot stamped parts are commonly made out of boron-manganese steel 22MnB5, which is initially austenized and subsequently formed and quenched in one process step. As a result, geometrical complex structures with an ultimate tensile strength of 1500 MPa are generated. The surfaces of the workpieces are coated with an Al-Si layer to avoid oxide scale formation and to ensure corrosion protection. However, the coating system leads to an increased adhesive wear on the tool surface due to the high thermo-mechanical tool stresses. Therefore, a time and cost consuming rework of the hot stamping tools is required. The aim of this study is to increase the tribological performance of hot stamping tools by using a laser implantation process. This technique allows the manufacturing of separated, elevated and dome-shaped microstructures on the tool surface in consequence of a localized dispersing of hard ceramic particles by pulsed laser radiation. The generated surface features offer great potential for reducing the tribological load, due to their high hardness and wear resistance. For this purpose, the friction coefficient of unmodified and laser implanted tool surfaces were examined and compared by using a modified pin-on-disk test. In addition, the surfaces were analyzed by optical measurements in order to quantify the amount of wear.<br

Tribological Properties of Ceramics after Machining with XeCl Excimer Laser Radiation. - Geiger, Manfred; Becker, Wolfgang (Production Engineering, 1996)
LFT Import::2019-07-15 (636)

Tribologische Eigenschaften keramischer Blechumformwerkzeuge - Einfluss einer Oberflächenendbearbeitung mittels Excimerlaserstrahlung - Neudecker, Thomas (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2004)
This thesis focuses on the influence of the surface finish of ceramic tools on their friction and wear properties. Surface finish is done by conventional methods (grinding, lapping and by excimer laser radiation (surface modification and micro texturing). Compared to conventional tool materials ceramics prove a distinctly higher wear resistance. Frictional properties are substantially determined by tool roughness. Influencing the tribological properties by an excimer laser treatment is very limite

Tribologische Eigenschaften von Keramikoberflächen nach einer Endbearbeitung mit Excimerlaserstrahlung - Geiger, Manfred; Hutfless, Joachim; Becker, Wolfgang; Tönshoff, H.-K.; Von Alvensleben, F.; Kappel., H. (Tagungsband zum Werkstoffkolloquium: Laserinduzierte Hochtemperatur-Werkstoffprüfung und -optimierung, 1995)
LFT Import::2019-08-05 (547)

Tribology and influence of tool coatings on frictional conditions within forming of advanced high strength steels - Merklein, Marion; Geiger, Manfred; Kaupper, Markus (Conference Proceedings, 7th International Conference THE Coatings, 2008)
LFT Import::2019-08-05 (205)

Tröpfchenschweißen - Laser Droplet Welding. Selektives Schweißverfahren mit Zusatzmaterial brigt enormes Potenzial - Jahrsdörfer, Bernd; Eßer, Gerd; Schmidt, Michael (Euro-Laser, 2004)
LFT Import::2019-07-16 (1099)

Überblick der Blechmassivumformung - Merklein, Marion; Opel, Simon; Schneider, Thomas; Koch, Johannes Peter Karl (Umformtechnik, 2012)
LFT Import::2019-07-29 (1788)

Über die Blechprüfung von heute - Merklein, Marion; Suttner, Sebastian; Hofmann, Maren; Kuppert, Andreas (Tagungsband Werkstoffprüfung, 2012)
LFT Import::2019-08-05 (1839)

UHS Steel Formability in Flexible Roll Forming - Mäntyjärvi, Kari; Merklein, Marion; Karjalainen, Jussi A. (Proceedings of the SheMet2009, 2009)
Ultra-high-strength (UHS) steels are very interesting materials for many applications where high strength can be utilized to create lighter and more effective constructions. The poor formability of UHS steels, however, may limit the usefulness of these materials in many applications. In this work, some experiments using a flexible roll forming machine developed at the Chair of Manufacturing Technology (LFT), University of Erlangen-Nuremberg were carried out using 4mm-thick bainitic martensitic UHS steels (YS/TS 960/1000 and 1100/1250) and the outcomes have been analysed. Results of these experimental tests show that using roll forming it is possible to bend test materials to an angle of 90° without damages with an evidently smaller radius than in air bending. The radius obtained using roll forming can be as small as 40% of the value used in air bending. Tests also show that with the method used in these tests it is possible to make roll forming for the whole length of the plate. The tests proved that the NC-controlled single-step roll forming method has potential for manufacturing small batches of bend profiles; however, more development has to be carried out if the process is to be made suitable for industry. © (2009) Trans Tech Publications, Switzerland.
LFT Import::2019-08-05 (1581)
Keywords: Bending; Roll forming; Ultra-high-strength steel

Ultraschallschneiden von kurzglasverstärkten PUR-Formteilen - Geiger, Manfred; van der Heyd, Gerhard; Müller, Roland (Kunststoffe, 1989)
LFT Import::2019-07-15 (434)

Ultraschallüberlagertes Umformen und Verstemmen von Stahlwerkstoffen - Leicht, Uwe (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2023)
The staking process is characterized by high process forces, which severely limit the use of the joining process. The superimposing of mechanical joining and forming processes with ultrasonics demonstrate great potential in reducing process forces, which could expand the process limits of the staking process. However, a lack of process knowledge has so far prevented the industrial application of ultrasonic superimposed processes. The central purpose of this thesis is a basic process understanding for the ultrasonic superimposed staking process on the high-alloy stainless steel and the identification of force-reducing mechanisms of the vibration superimposition. In the experiment, the superimposed ultrasonics led to a reduction in the process force up to 59 % and still having a comparable joint strength. Dynamic influences via the superposition principle and tribological influences due to reduced surface friction could be proven to be the decisive mechanisms for the force reduction. In addition, the slight wobbling movement of the forming punch ensures an additional reduction in the process force. The reduced staking force during establishing the joint connection in combination with the comparable resilience offers the considerable potential of expanding the process limi

Ultraschallunterstütztes Umformen und Verstemmen - Aktuelle Ergebnisse aus dem Verbundprojekt "UltraCaulk" - Leicht, U.; Michalski, Markus; Merklein, Marion (wt Werkstattstechnik - Online, 2017)
Substantial force reductions can be achieved by superimposing high frequency oscillation on forming processes. The joint research project UltraCaulk focusses on fundamental investigations on the material flow behaviour during ultrasonic influence and the transferability of identified mechanisms on industrial caulking processes. This study analyses the influence of process parameters on the resulting force reduction and specimen heating.
LFT Import::2019-07-29 (2199)

Ultraschallunterstützte Umformung von Metallen - Entwicklung eines Prüfstands zur Werkstoffcharakterisierung mit 15 kHz Schwingungsüberlagerung - Michalski, Markus; Merklein, Marion (wt Werkstattstechnik - Online, 2015)
LFT Import::2019-07-29 (2120)

Ultrasonic-assisted forming - Influence of unavoidably induced tool oscillations - Jäckisch, Manuel; Merklein, Marion (XL. Conference on Metal Forming, 2022)
Enhanced material strengths and a growing demand for complex part geometries lead to elevated process forces in cold forming processes and in turn to increased tool wear. One approach to face these challenges is the application of ultrasonic-assistance. By superimposing a high frequency oscillation to the tool movement, the material’s flow stress is reduced immediately and forming with lower process forces is feasible. This beneficial softening enhances with increasing vibrational energy input. Thus, the oscillation amplitude has been determined as the crucial process parameter for the achievable force reduction. When superimposing the punch with a high frequency oscillation, the vibration is introduced not only into the workpiece itself, but also through it into the fixed die. Consequently, moderate unavoidable oscillations occur in the fixed tool. In dependency of the phase shift between the oscillating tools, the nominal amplitude can be amplified or weakened. Nevertheless, most studies focused merely on the nominal amplitude. Within this contribution ultrasonic-assisted compression testing with pure copper Cu-OFE and brass CuZn37 is carried out and the oscillations of the upper and lower tool are measured synchronously. Significant deviations between the introduced and the effective oscillation are determined, leading to alternated process parameters.<br
Keywords: ultrasonic; metal forming; measurement; tool

Ultrasonic-Assisted Upsetting of Steel with 15 kHz Oscillation Frequency - Michalski, Markus; Merklein, Marion (Key Engineering Materials, 2016)
LFT Import::2019-07-29 (2170)
Keywords: Cold Forming; Metal; Ultrasonic

Ultrasonic Inspection of Cold Forging Tools - Geiger, Manfred; Putz, Alexander; Engel, Ulf (Production Engineering - Annals of the WGP, 2006)
LFT Import::2019-08-05 (1265)

Ultrasonic Inspection of Prestressed Cold Forging Tools - Development of a Theoretical Model and Relevance for Industry - Putz, Alexander (Wire, 2006)
LFT Import::2019-07-16 (1255)

Ultrasonic Inspection of Stress State of Prestressed Extrusion Dies - Geiger, Manfred; Engel, Ulf; Pfestorf, Markus (Production Engineering, 1994)
LFT Import::2019-07-15 (467)

Ultrasonic inspection of the real prestressing conditions of cold forging tools - Putz, Alexander; Engel, Ulf (New developments in forging technology, 2005)
LFT Import::2019-07-16 (1244)

Ultrasonic Inspection of Tooling Systems in Cold Forging - Falk, Bernd; Putz, Alexander; Engel, Ulf (Proceedings of the 3rd International Conference on Industrial Tools (ICIT), 2001)
LFT Import::2019-08-05 (876)

Ultrasonic Investigation of Friction Mechanism in Metal Forming - Niederkorn, Sorin; Engel, Ulf; Geiger, Manfred (Journal of Materials Processing Technology, 1994)
A newly developed friction and lubrication test is used to examine the quantitative relation between real contact area (r.c.a.) and coefficient of friction in metal forming processes. The first part of the paper will give a description of the experimental set-up. It enables the in-situ ultrasound measuring of the r.c.a. simultaneously to the measuring of the friction coefficient in the second part the relation between r.c.a. and the coefficient of friction is analysed, using a ring and a closed-die upsetting test to determine the coefficient of friction, each combined with the ultrasound method for measuring the r.c.a. © 1994.
LFT Import::2019-07-15 (625)

Ultrasonic Measurement of the Real Contact Area between Die and Ring in Prestressed Cold Forging Tools - Putz, Alexander; Engel, Ulf; Geiger, Manfred (ISPF 2004, Proceedings of the 3rd JSTP International Seminar on Precision Forging, 2004)
LFT Import::2019-08-05 (1025)

Ultrasound-assisted material characterization: An innovative method for the non-destructive in-situ detection of microstructural changes of high-strength aluminum alloys - Rigas, Nikolaos; Lypchanskyi, Oleksandr; Prahl, Ulrich; Merklein, Marion (Journal of Materials Processing Technology, 2024)
The use of aluminum alloys in conjunction with thermal-assisted forming techniques permits the production of high-strength and geometrically complicated components without failure. By using innovative, temperature-dependent production techniques, it is possible to manufacture components with tailored properties. So far, however, it is not possible to characterize the microstructural behavior under thermal and mechanical load in real-time. Using a novel characterization method, which is based on the principle of laser ultrasonic testing, it has become possible to record contact-free and non-destructive microstructural changes in-situ during thermo-mechanical treatment. This allows the interaction-free detection of thermal as well as mechanical effects during thermal-supported forming operations. In this research work, the temperature-dependent behavior during the quenching and aging process of the precipitation-hardenable aluminum alloy AA6082 for a tailor-quenched forming process is recorded in real-time using laser ultrasonic techniques. First, the effects of different tool temperatures on quenching rates and material properties were investigated using conventional characterization methods, including temperature measurement, hardness and tensile tests. It was shown that a die temperature of 325 °C leads to the lowest material hardness and strength. Subsequently, the results were compared with the novel, non-destructive in-situ testing method and validated using microstructural analysis. It was proven, that microstructural changes can be identified during varying quench and aging operations. Thus, the influence of different process parameters on the microstructural and mechanical development of aluminum components can be detected in-situ for the first time.
Keywords: Tailor Quenched Forming; High-strength aluminum; In-situ characterization; LUMet; Precipitation behavior

Umformen von Magnesiumblechen im Doppelpack - Merklein, Marion; Hußnätter, Wolfgang (Maschinenmarkt, 2007)
LFT Import::2019-07-16 (1400)

Umformtechnik auf der 43. CIRP-Generalversammlung - Geiger, Manfred; Coremans, Adrianus (Blech, Rohre, Profile, 1994)
LFT Import::2019-07-15 (388)

Umformtechnische Herstellung dünnwandiger Funktionsbauteile aus Feinblech durch Verfahren der Blechmassivumformung - Schneider, Thomas (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2016)
The major objective of the work is to generate a holistic understanding of manufacturing thin-walled functional components out of sheet metal by Sheet-bulk metal forming in order to increase the technical opportunities of metal forming processes. In this context, the potential of single-stage process strategies combining conventional deep drawing and upsetting is identified. The component quality and the resource efficiency can be improved by suitable selection of technical parameters and by application of innovative process strategies using tailored blanks and tailored surface

Umformtechnische Herstellung kleiner Bauteile - Siegert, K.; Frank, H.; Geiger, Manfred; Eckstein, Ralf; Neugebauer, R.; Schubert, A.; Böhm, J. (FTK 2000 - Fertigungstechnisches Kolloquium. Schriftliche Fassung der Vorträge zum Fertigungstechnischen Kolloquium am 26./27. September 2000 in Stuttgart, 2000)
LFT Import::2019-08-05 (803)

Umformtechnische Herstellung metallischer Kleinstteile - Geiger, Manfred; Engel, Ulf; Eckstein, Ralf; Tiesler, Nicolas (Sonderforschungsbereich 356 Produktionssysteme in der Elektronik, 2001)
LFT Import::2019-08-05 (847)

Umformtechnische Herstellung metallischer Kleinstteile - Werkstoffverhalten und Wirkflächenreibung - Geiger, Manfred; Meßner, Arthur; Engel, Ulf (Tagungsband zur 2. Sächsischen Fachtagung Umformtechnik, 1995)
LFT Import::2019-08-05 (549)

Umformtechnische Herstellung von Funktionsbauteilen aus Tailored Blanks durch Blechmassivumformverfahren - Schulte, Robert Karl; Lechner, Michael; Vogel, Manfred; Hildenbrand, Philipp; Merklein, Marion (22. Umformtechnisches Kolloquium Hannover – Innovationspotentiale in der Umformtechnik. 15./16.03.2017, 2017)
LFT Import::2019-08-05 (2230)

Umformtechnische Strukturierung metallischer Einleger im Folgeverbund für mediendichte Kunststoff-Metall-Hybridbauteile - Frey, Philipp (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2022)
Eine wesentliche Herausforderung bei der Herstellung von Kunststoff-Metall-Hybridbauteilen im Montagespritzguss ist die eingeschränkte Mediendichtheit aufgrund der chemischen Inkompatibilität der beiden Werkstoffe. Der Einsatz strukturierter, metallischer Einleger hat in diesem Zusammenhang ein großes Potential die Dichtheit zu steigern. Im Rahmen dieser Arbeit wird daher die umformtechnische Strukturierung metallischer Einleger im Folgeverbundwerkzeug als hoch effizientes Fertigungsverfahren untersucht. Ziel dieser Arbeit ist ein Verständnis für die Herstellbarkeit strukturierter Einleger aufzubauen und die Prozessgrenzen abzuleiten im Hinblick auf die funktionsgerechte Auslegung. Anhand der Untersuchungen zum Verrunden der Schnittkanten mittels Prägen wurde die Querschnittsfläche des Einlegers als wichtigste Einflussgröße auf die Formfüllung und somit auf die Abbildungsgenauigkeit identifiziert. Bei den Untersuchungen zum Einprägen von Quernuten in die Einlegeroberfläche konnte durch die Gliederung des Werkstoffflusses in axiale und laterale Richtung, ein ganzheitliches Verständnis hinsichtlich der Ausformung der Nuten sowie der Längung und Breitung der Einleger geschaffen werden. Gerade die Breitung wird in diesem Zusammenhang durch die vorherrschenden Fließbehinderungen stark beeinflusst. Abschließend wurden die Untersuchungsergebnisse der umformtechnischen Strukturierung anhand der resultierenden Dichtheit umspritzter Einleger eingeordnet und eine Erhöhung der Dichtwirkung aufgezeigt. Dadurch wird ein Beitrag zur Entwicklung und Fertigung widerstandfähiger elektronischer Systeme geleiste

Umform- und Rückfederungssimulation von Leichtbauwerkstoffen - Vergleichende Betrachtung von Zug-Druck- und Wechselbiegeversuchen zur Berücksichtigung des Bauschinger-Effekts - Wieland, Michael; Kaupper, Markus; Merklein, Marion (Tagungsband des 33. EFB-Kolloquiums Blechverarbeitung, 2013)
LFT Import::2019-08-05 (1887)

Umformung von Tailored Heat Treated Blanks aus Aluminium - Merklein, Marion; Geiger, Manfred (Metall, 2006)
LFT Import::2019-07-16 (1300)

Umformwerkzeuge in der Blechmassivumformung - Biermann, D.; Merklein, Marion; Engel, Ulf; Tillmann, W.; Surmann, T.; Hense, R.; Herper, J.; Koch, Johannes Peter Karl; Krebs, E.; Vierzigmann, Ulrich (1. Workshop Blechmassivumformung, 2011)
LFT Import::2019-08-05 (1777)

Unsupervised Deep Learning for Advanced Forming Limit Analysis in Sheet Metal: A Tensile Test-Based Approach - Thamm, Aleksandra; Thamm, Florian; Sawodny, Annette; Zeitler, Sally; Merklein, Marion; Maier, Andreas (Materials, 2023)
An accurate description of the formability and failure behavior of sheet metal materials is essential for an optimal forming process design. In this respect, the forming limit curve (FLC) based on the Nakajima test, which is determined in accordance with DIN EN ISO 12004-2, is a wide-spread procedure for evaluating the formability of sheet metal materials. Thereby the FLC is affected by influences originating from intrinsic factors of the Nakajima test-setup, such as friction, which leads to deviations from the linear strain path, biaxial prestress and bending superposition. These disadvantages can be circumvented by an alternative test combination of uniaxial tensile test and hydraulic bulge test. In addition, the forming limit capacity of many lightweight materials is underestimated using the cross-section method according to DIN EN ISO 12004-2, due to the material-dependent occurrence of multiple strain maxima during forming or sudden cracking without prior necking. In this regard, machine learning approaches have a high potential for a more accurate determination of the forming limit curve due to the inclusion of other parameters influencing formability. This work presents a machine learning approach focused on uniaxial tensile tests to define the forming limit of lightweight materials and high-strength steels. The transferability of an existing weakly supervised convolutional neural network (CNN) approach was examined, originally designed for Nakajima tests, to uniaxial tensile tests. Additionally, a stereo camera-based method for this purpose was developed. In our evaluation, we train and test materials, including AA6016, DX54D, and DP800, through iterative data composition, using cross-validation. In the context of our stereo camera-based approach, strains for different materials and thicknesses were predicted. In this cases, our method successfully predicted the major strains with close agreement to ISO standards. For DX54D, with a thickness of 0.8 mm, the prediction was 0.659 (compared to ISO’s 0.664). Similarly, for DX54D, 2.0 mm thickness, the predicted major strain was 0.780 (compared to ISO 0.705), and for AA6016, at 1.0 mm thickness, a major strain of 0.314 (in line with ISO 0.309) was estimated. However, for DP800 with a thickness of 1.0 mm, the prediction yielded a major strain of 0.478 (as compared to ISO 0.289), indicating a divergence from the ISO standard in this particular case. These results in general, generated with the CNN stereo camera-based approach, underline the quantitative alignment of the approach with the cross-section metho
Keywords: forming limit curve; pattern recognition; sheet metal forming; machine learning

Untersuchung der Prozesseinflussgrößen beim Presshärten des höchstfesten Vergütungsstahls 22MnB5 - Hoff, Cornelia (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2007)
Within the thesis the main influencing parameters during the different process steps of the hot stamping process as well as their interaction is examined. Emphasis is laid on the investigation of the heat transfer between blank and tool and the determination of the heat transfer coefficient during the different contact situations. In addition to that the characterization of the material properties of the steel 22MnB5 under the specific conditions of the hot stamping process is another focus of the wor

Untersuchung der Reibbedingungen beim Presshärten mittels Streifenziehversuchen bei erhöhten Temperaturen - Schwingenschlögl, Patrik; Hildering, Sven; Merklein, Marion (10. Erlanger Workshop Warmblechumformung, 2015)
LFT Import::2019-08-05 (2129)

Untersuchung der thermo-mechanischen Fließeigenschaften presshärtbarer Stähle - Merklein, Marion; Lechler, Jürgen; Geiger, Manfred; Kleiner, M.; Karbasian, H.; Homberg, W. (Proceedings of the 2nd International Conference on Accuracy in Forming Technology ICAFT 2006, in Verbindung mit 13. sächsische Fachtagung Umformtechnik SFU 2006, 2006)
LFT Import::2019-08-05 (1341)

Untersuchung der Werkzeugbeanspruchung und des Verschleißes beim Schneidclinchen - Wiesenmayer, Sebastian; Han, D.; Meschut, G.; Merklein, Marion (XXXVIII. Verformungskundliches Kolloquium, 2019)
LFT Import::2019-08-05 (2360)

Untersuchung des Einflusses von Chargenschwankungen auf das Umwandlungsverhalten übereutektoider Stähle - Lutz, Stefan; Weninger, J.; Helldörfer, B.; Merklein, Marion (Tagungsband Werkstoffprüfung, 2014)
LFT Import::2019-08-05 (2063)

Untersuchung des Einflusses von werkstückseitigen Parametern auf die Schichtausbildung von zinkbeschichtetem Bor-Manganstahl - He, Franz; Merklein, Marion (Warmumformung von höchstfesten Vergütungsstählen: Tagungsband zum 16. Erlanger Workshop Warmblechumformung, 2021)
Das Presshärteverfahren hat sich als Technologie zur Herstellung von höchstfesten Stahlwerkstoffen für sicherheitsrelevante Bauteile im Karosserieleichtbau etabliert. Durch ihren Einsatz lassen sich aufgrund reduzierter Blechdicke in Kombination mit hohen Zugfestigkeiten Leichtbaukonzepte bei gleichzeitig verbessertem Crashverhalten realisieren. Dabei kommen für gewöhnlich Bor-Mangan-Stähle zum Einsatz. Aufgrund von Prozesstemperaturen über 800 °C gilt das Presshärten als schmierstofffreies Verfahren. Neben hoher Reibung und Verschleiß im Prozess sind Oberflächenverzunderung und Nachbearbeitung die Folge. Zum Schutz vor Korrosion werden Presshärtewerkstoffe deswegen beschichtet. Bisher kamen hauptsächlich Beschichtungen auf Aluminium-Silizium-Basis für das direkte Presshärten zum Einsatz. Während Beschichtungen auf Zink-Basis bisher vorwiegend im indirekten Prozessablauf Anwendung fanden, erschließt sich diese inzwischen auch für die direkte Verfahrensroute. In vorherigen Untersuchungen konnte für Aluminium-Silizium (AlSi) Beschichtungen ein signifikanter Einfluss von werkstückseitigen Parametern auf die Ausbildung der Beschichtung während des Austenitisierungsprozesses festgestellt werden. Vor diesem Hintergrund wird ein ähnlich signifikanter Einfluss für Beschichtungen auf Zink-Basis vermutet. Im Zuge dessen sollen die Parameter Aufheizrate, Ofentemperatur und Ofenverweilzeit und die Auswirkung auf die Schichtausbildung von zinkbeschichteten 20MnB8 während der Austenitisierung untersucht werden. Die sich daraus ergebenden Erkenntnisse bilden die Basis für weiterführende Versuche, um den tiefergehenden Einfluss der Parameter auf Reibung und Verschleiß im industrienahen Streifenzugversuch zu untersuchen. <
Keywords: Zinkbeschichtung; 20MnB8; Direktes Presshärten

Untersuchung des Einsatzverhaltens kaltfließgepresster Zahnräder - Rohrmoser, Andreas; Kiener, Christoph; Hagenah, Hinnerk; Merklein, Marion (34. Jahrestreffen der Kaltmassivumformer, 2019)

Untersuchung des kombinierten Trenn- und Umformprozesses beim Fügen artungleicher Werkstoffe mittels Schneidclinchverfahren - Müller, Martin (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2019)
Legal necessities for a reduction of CO2 emissions as well as increasing customer demands for comfort require an ongoing development of drive and car body concepts. One of the most important approaches regarding the body in white construction is the consequent implementation of lightweight materials. The combination of high-strength steel materials and nonferrous metals allows a weight reduction without decreasing crash-performance of the car. The high yield strength and low formability as well as the increase in the number of components and materials are major challenges for adapted joining technologies. The shear-clinching process offers great potential in this field of application. The combination of a cutting and a forming operation in a single stage process allows the joining of aluminum and ultra-high-strength steel sheets without a pre-holing operation or any auxiliary part. In this context, this scientific work elaborated a comprehensive process understanding of the subprocesses and the combined shear-clinching technology. For this purpose, an adapted tool system as well as a damage-based numerical model of the cutting process were developed, based on previous investigations on the qualification of the shear-clinching process. Subsequently, numerical and experimental analyses of the subprocesses as well as experimental parameter studies were carried out. The results were used to identify effects on the shear-clinching joint as well as to develop guidelines for the practical application of the shear-clinching proces

Untersuchung des tribologischen Einsatzverhaltens von lokal dispergierten Presshärtewerkzeugoberflächen - Schirdewahn, Stephan; Spranger, Felix; Hilgenberg, Kai; Merklein, Marion (14. Erlanger Workshop Warmblechumformung, 2019)
Das Presshärteverfahren hat sich zur ressourceneffizienten Verarbeitung von höchstfesten Stahlwerkstoffen im Karosserieleichtbau weltweit etabliert. Die fehlerfreie Bauteilproduktion wird jedoch durch Reibungs- und Verschleißerscheinungen aufgrund hoher thermo-mechanischer Werkzeugbelastungen und fehlender Schmierstoffsysteme limitiert. Als Lösungsansatz wird eine Modifikation der Werkzeugoberfläche mittels Laserimplantation angestrebt, um folglich deren Verschleißbeständigkeit nachhaltig zu erhöhen. Das Verfahren basiert auf einem lokalen Dispergieren keramischer Hartstoffpartikel in die Werkzeugoberfläche, infolgedessen hochfeste und erhabene Strukturen im Mikrometerbereich entstehen. Aufgrund der signifikanten Reduzierung der Kontaktfläche sowie der hohen Verschleißbeständigkeit der eingesetzten TiB2-Hartstoffe wird ein verbessertes tribologisches Einsatzverhalten unter presshärtetypischen Prozessbedingungen erwartet. Zur Verifizierung dieser Annahmen wurden im Rahmen dieser Arbeit modifizierte Pin-on-Disk Tests durchgeführt, um das Reib- und Verschleißverhalten der laserimplantierten Werkzeugoberflächen unter Presshärtebedingungen zu untersuchen. Zur weiteren Vertiefung des Prozess-verständnisses wurden die verschlissenen Platinen via Tastschnittmessungen und Querschliffaufnahmen analysiert. Durch den Ergebnisvergleich mit konventionellen Werkzeugoberflächen erfolgte eine abschließende Bewertung des tribologischen Einsatzverhaltens der laserimplantierten Strukturen.<br
Keywords: Presshärten; Laserimplantation; Tribologie; 22MnB5

Untersuchung einer thermisch unterstützten Fertigungskette zur Herstellung umgeformter Bauteile aus der höherfesten Aluminiumlegierung EN AW-7020 - Unger, Nora (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2017)
This book presents the fundamentals for the production of formed components from the high-strength aluminum alloy EN AW-7020 using the retrogression and reaging treatment (RRA). The transferability to an overall production chain with integration of the forming process into the course of RRA treatment is discussed. For this purpose, the mechanical material behavior as well as the corrosion behavior are characterized according to the respective process steps in order to elaborate an overall process window in the examined limits for temperature and time during the RRA treatmen

Untersuchungen der Effekte und Wechselwirkungen charakteristischer Einflussgrößen auf das Umformverhalten bei Mikroumformprozessen - Eichenhüller, Bernd (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2014)
The miniaturizing of products and technical systems is a known trend in various areas of application. Microforming is not established for the mass production of smallest metallic parts up to date, due to the occurrence of size effects. This book shows the impact of effects and interactions on the forming behavior induced by miniaturizing the forming: proces

Untersuchungen hinsichtlich der Eignung von EN AW 1050 für die Herstellung prismatischer Bauteile mittels Napf-Rückwärts-Fließpressen - Austen, M.; Klonczynski, A.; Derenthal, M.-J.; Noneder, Johannes; Merklein, Marion (UTF-Science, 2013)
LFT Import::2019-07-29 (1906)

Untersuchungen von Tailored Surfaces für die Blechmassivumformung mittels angepasstem Ringstauchversuch - Vierzigmann, Ulrich; Schneider, Thomas; Koch, Johannes Peter Karl; Gröbel, Daniel; Merklein, Marion; Engel, Ulf; Hense, R.; Biermann, D.; Krebs, P.; Kersting, P.; et al. (2. Workshop Blechmassivumformung, 2013)
LFT Import::2019-08-05 (1926)

Untersuchungen zum Biegeumformen mit elastischer Matrize - Ende, Arnold (Friedrich-Alexander-Universität Erlangen-Nürnberg, 1991)

Untersuchungen zur Anlagen- und Prozeßdiagnostik für das Schneiden mit CO2-Hochleistungslasern - Biermann, Stephan (Friedrich-Alexander-Universität Erlangen-Nürnberg, 1991)
In this work the main measurable variables of machine and process diagnostics for high power CO2 laser cutting were, for the first time, compiled in context and discussed regarding their impact on process quality. Above all the properties of the laser beam and process gas stream and the temperature distribution in the workpiece were experimentally investigated. A range of self designed and also commercially available diagnostic equipment was used on a conventional laser beam cutting machine. Simultaneously a technological investigation of laser beam cutting of metals was carried to detect the impact of the measurable variables on process quality. With that a basis was established for the future realization of online process diagnostics and closed-loop control system

Untersuchungen zur Bearbeitungsqualität im Fertigungssystem Laserstrahlschneiden - Nuss, Rudolf (Friedrich-Alexander-Universität Erlangen-Nürnberg, 1989)
This research enlarged the knowledge concerning the quality determining influencing variables during laser beam cutting and to set the stage for an optimal process management and its realization. For the first time the significant interactions within the manufacturing system laser beam cutting were taken into account. This was possible by applying a specifically created laser beam- and process diagnostics system, which allowed to correlate local cut surface criteria with present process parameters and resulting surface properties. Taking into consideration the different geometrical elements a test workpiece was developed, on the basis of which it was possible to scientifically prove that, among other things, the achievable machining accuracy within the laser beam cutting enables the fabrication of finished part

Untersuchungen zur Erhöhung der Prozessrobustheit bei der Innenhochdruck-Umformung von flächigen Halbzeugen mit vor- bzw. nachgeschalteten Laserstrahlfügeoperationen - Blankl, Andreas (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2009)
The scope of this work was the generation of fundamental basics to design robust process chains under the participation of hydroforming and laser processing steps to manufacture high quality sheet metal parts in a low and middle volume production. Therefore a suitable process chain was determined and investigated with Failure Method and Effect Analysis (FMEA) in order to increase the process robustness. The detected weak spots were investigated more closely and suitable strategies to increase the robustness of the whole process chain were determined. In particular results of basic investigations of leakage phenomena in double sheet hydroforming are presented. Furthermore several strategies for laser welding contaminated sheets in overlap configuration are discussed and compared to each other on the basis of experimental results. Finally a new method for designing laser annealing processes is presented and verified on experimental investigations of laser welded dual phase steel sheet

Untersuchungen zur Herstellung von funktionsoptimierten Bauteilen im partiellen Presshärtprozess mittels lokal unterschiedlich temperierter Werkzeuge - Svec, Thomas (2015)
The objective of this work is to manufacture functionally optimized components with locally adjusted mechanical properties in partial hot stamping process by controlling the cooling conditions using locally different heated tools. The influence of forming process at elevated temperatures and the relationships between material and process parameters on the thermal processes and the resulting mechanical properties are investigated and characteristic values are verified by numerical calculation

Untersuchungen zur Stoffflusssteuerung beim Fügen durch Umformen von hochfesten Aluminiumlegierungen mittels lokaler Kurzzeitwärmebehandlung - Wiesenmayer, Sebastian (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2024)
Mechanische Fügeprozesse nehmen eine wichtige Rolle bei der Herstellung von Fahrzeugkarosserien in Mischbauweise ein. Aufgrund der hohen Festigkeit und der meist eingeschränkten Umformbarkeit moderner Hochleistungswerkstoffe stoßen etablierte Fügeverfahren an ihre Grenzen. Dies gilt insbesondere für das Fügen hochfester AlZnMg-Legierungen der 7000er Serie. Durch eine Wärmebehandlung können die Eigenschaften der ausscheidungshärtbaren Legierungen angepasst und die Umformeigenschaften verbessert werden. Wird die Wärmebehandlung lokal begrenzt, kann der Stofffluss bei Umformprozessen durch die Interaktion fester sowie entfestigter Bereiche gesteuert werden. Ziel der vorliegenden Arbeit war es, die Steuerung des Stoffflusses beim Fügen durch Umformen von 7000er Aluminium mittels einer prozessangepassten, lokal begrenzten Kurzzeitwärmebehandlung grundlegend zu erforschen und ein umfassendes Prozessverständnis abzuleiten. Zu diesem Zweck wurde der Einfluss von kurzzeitigem Rückbildungsglühen der Aluminiumlegierung EN AW-7075 T6 auf deren mechanische Eigenschaften ermittelt und die Prozessgrenzen beim Fügen der Legierung im Schneidclinchprozess bei matrizenseitiger Anordnung von 22MnB5 und HCT780X bestimmt. Unter Variation der Wärmebehandlungsparameter wurden punkt- und ringförmige Layouts gegenübergestellt und deren Einfluss auf den Fügeprozess und die Einsatzeigenschaften der Fügepunkte untersucht. Da der Werkstoff nach dem Rückbildungsglühen wiederauslagert, stellte die Analyse der Einsatzeigenschaften der Fügepunkte nach einer Warmauslagerung sowie der Wechselwirkung mit der dem Fügen vorgelagerten Wärmebehandlung einen weiteren Schwerpunkt der Arbeit da

Untersuchungen zur Umformbarkeit hybrider Bauteile aus Blechgrundkörper und additiv gefertigter Struktur - Papke, Thomas (Friedrich-Alexander-Universität Erlangen-Nürnberg, 2022)
An efficient use of resources has become increasingly important in recent years due to a growing world population and rising demand for consumer goods. This requires more sustainable and more flexible industrial production processes. One strategy to cope with these challenges is the use of newly developed manufacturing processes such as additive manufacturing. Additive manufacturing offers enormous potential for flexibilization and individualizing of products with increased added value. However, nowadays this is associated with longer production times and lower productivity at high volumes compared to conventional processes such as forming. The combination of additive manufacturing and forming for the production of hybrid components enables exploiting the specific advantages of both technologies. The aim of this work is to receive a fundamental understanding of the formability of hybrid components. The investigations start with the systematic analysis of influencing variables in the production of additively manufactured structures on a sheet metal base body by powder-bed fusion using a laser beam (PBF-LB/M). Then the hybrid components are characterized regarding their mechanical properties and grain structure. Formability of hybrid parts is evaluated by free bending. This allows the forming to be analyzed in terms of geometry, strain distribution, material flow and stress state. Finally, the knowledge gained is transferred to a demonstrator part and potentials for industrial application are identifie