TY - CHAP
T1 - Machining Versus Heat Treatment in Additive Manufacturing of Ti6Al4V Alloy
AU - Dareh Baghi, Alireza
AU - Nafisi, Shahrooz
AU - Hashemi Oskouei, Reza
AU - Ebendorff-Heidepriem, Heike
AU - Ghomashchi, Reza
PY - 2022/2/7
Y1 - 2022/2/7
N2 - Anisotropy in the mechanical properties of Laser Powder Bed Fusion (L-PBF)-fabricated titanium parts, which could be problematic in service, is dependent on the build directions and may be mitigated by post-fabrication treatments such as surface machining or heat treatment. However, investigation of the anisotropy in truly as-printed conditions, i.e., prior to any post-process, is always a challenge as the horizontally built parts are noticeably distorted compared to vertically built ones. In this study, by deploying a novel design, straight horizontal samples in the as-printed condition were fabricated. This allowed a comparison to be made possible in the mechanical properties of two built orientations of vertical and horizontal in the as-printed condition. This paper discusses how the surface machining or post-thermal treatment influences the anisotropy in the mechanical properties compared to as-printed conditions. It further highlights how annealing process at a temperature of 850 °C is more effective than stress relieving at a temperature of 670 °C to nearly diminish the anisotropy in mechanical properties even without any need for machining. Therefore, when machining becomes less feasible due to the geometrical complexity of L-PBF parts, a thermal treatment may be the solution for better service performance.
AB - Anisotropy in the mechanical properties of Laser Powder Bed Fusion (L-PBF)-fabricated titanium parts, which could be problematic in service, is dependent on the build directions and may be mitigated by post-fabrication treatments such as surface machining or heat treatment. However, investigation of the anisotropy in truly as-printed conditions, i.e., prior to any post-process, is always a challenge as the horizontally built parts are noticeably distorted compared to vertically built ones. In this study, by deploying a novel design, straight horizontal samples in the as-printed condition were fabricated. This allowed a comparison to be made possible in the mechanical properties of two built orientations of vertical and horizontal in the as-printed condition. This paper discusses how the surface machining or post-thermal treatment influences the anisotropy in the mechanical properties compared to as-printed conditions. It further highlights how annealing process at a temperature of 850 °C is more effective than stress relieving at a temperature of 670 °C to nearly diminish the anisotropy in mechanical properties even without any need for machining. Therefore, when machining becomes less feasible due to the geometrical complexity of L-PBF parts, a thermal treatment may be the solution for better service performance.
KW - Laser powder bed fusion
KW - Ti6Al4V
KW - Build direction
KW - Machining
KW - Stress relieving
KW - Annealing
UR - http://www.scopus.com/inward/record.url?scp=85125255510&partnerID=8YFLogxK
U2 - 10.1007/978-3-030-92381-5_17
DO - 10.1007/978-3-030-92381-5_17
M3 - Chapter
SN - 978-3-030-92380-8
T3 - Minerals, Metals and Materials Series
SP - 187
EP - 197
BT - TMS 2022 151st Annual Meeting and Exhibition Supplemental Proceedings
A2 - The Minerals, Metals & Materials Society,
PB - Springer Link
ER -