Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting

Journal article
(Original article)


Publication Details

Author(s): Parsa AB, Ramsperger M, Kostka A, Somsen C, Körner C, Eggeler G
Journal: Metals
Publisher: MDPI AG
Publication year: 2016
Volume: 6
Journal issue: 11
ISSN: 2075-4701
Language: English


Abstract


In this work, the microstructures of superalloy specimens produced using selective electron beam melting additive manufacturing were characterized. The materials were produced using a CMSX-4 powder. Two selective electron beam melting processing strategies, which result in higher and lower effective cooling rates, are described. Orientation imaging microscopy, scanning transmission electron microscopy and conventional high resolution transmission electron microscopy are used to investigate the microstructures. Our results suggest that selective electron beam melting processing results in near equilibrium microstructures, as far as γ′ volume fractions, the formation of small amounts of TCP phases and the partitioning behavior of the alloy elements are concerned. As expected, higher cooling rates result in smaller dendrite spacings, which are two orders of magnitude smaller than observed during conventional single crystal casting. During processing, columnar grains grow in <100> directions, which are rotated with respect to each other. There are coarse γ/γ′ microstructures in high angle boundary regions. Dislocation networks form low angle boundaries. A striking feature of the as processed selective electron beam melting specimens is their high dislocation density. From a fundamental point of view, this opens new possibilities for the investigation of elementary dislocation processes which accompany solidification.



FAU Authors / FAU Editors

Körner, Carolin Prof. Dr.-Ing.
Lehrstuhl für Werkstoffwissenschaften (Werkstoffkunde und Technologie der Metalle)
Ramsperger, Markus
Lehrstuhl für Werkstoffwissenschaften (Werkstoffkunde und Technologie der Metalle)


How to cite

APA:
Parsa, A.B., Ramsperger, M., Kostka, A., Somsen, C., Körner, C., & Eggeler, G. (2016). Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting. Metals, 6(11). https://dx.doi.org/10.3390/met6110258

MLA:
Parsa, Alireza B., et al. "Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting." Metals 6.11 (2016).

BibTeX: 

Last updated on 2018-19-04 at 03:52