Mitigating overheating in complex Inconel 718 geometries through feedback loop control with ring-core beam shapes in PBF-LB/M
Novotny T, Mirzabeigi N, Kunz D, Kleinhans U, Bartels D (2026)
Publication Type: Conference contribution
Publication year: 2026
Journal
Publisher: Elsevier B.V.
Book Volume: 143
Pages Range: 701-706
Conference Proceedings Title: Procedia CIRP
Event location: Heinrich-Lades-Halle, DEU
DOI: 10.1016/j.procir.2026.07.146
Abstract
The laser-based powder bed fusion (PBF-LB/M) process is well suited to the production of complex geometries with high freedom of design due to its layer-by-layer manufacturing approach. However, geometric features such as overhangs can induce heat accumulation during processing and lead to variations in microstructure. To achieve consistent properties in complex parts, the energy input needs to be locally adjusted to the thermal conditions. While monitoring-based feedback loop control systems, such as Smart Fusion, have proven effective in homogenizing microstructures, testing has only been conducted on few materials using Gaussian beam profiles. Different intensity distributions warrant additional investigation as they influence the thermal emission and process window, which affects the monitoring and the controller, as well as the microstructure formation. In this study, the effect of feedback loop control on the overheating behavior of Inconel 718 is investigated for a standard Gaussian process and a process using a ring-shaped intensity distribution. A complex geometry prone to heat accumulation is manufactured with both processes and its thermal history, density, grain structure and hardness is compared between the uncontrolled (open-loop) and feedback-loop-controlled conditions. While severe overheating is found in uncontrolled condition, the controlled specimens exhibited a consistent thermal history and maintained high density. For the standard Gaussian process, the controller prevents hardness variations caused by in-situ heat treatment without notable alterations to the typical grain structure and size. Processing with the ring mode lead to consistent hardness in both control conditions while grain sizes varied depending on the location and application of feedback loop control.
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Germany (DE)How to cite
APA:
Novotny, T., Mirzabeigi, N., Kunz, D., Kleinhans, U., & Bartels, D. (2026). Mitigating overheating in complex Inconel 718 geometries through feedback loop control with ring-core beam shapes in PBF-LB/M. In Procedia CIRP (pp. 701-706). Heinrich-Lades-Halle, DEU: Elsevier B.V..
MLA:
Novotny, Tobias, et al. "Mitigating overheating in complex Inconel 718 geometries through feedback loop control with ring-core beam shapes in PBF-LB/M." Proceedings of the 14th CIRP Conference on Photonic Technologies, LANE 2026, Heinrich-Lades-Halle, DEU Elsevier B.V., 2026. 701-706.
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