TY - JOUR
T1 - LPBF Processability of NiTiHf Alloys
T2 - Systematic Modeling and Single-Track Studies
AU - Dabbaghi, Hediyeh
AU - Pourshams, Mohammad
AU - Nematollahi, Mohammadreza
AU - Poorganji, Behrang
AU - Kirka, Michael M.
AU - Smith, Scott
AU - Chinnasamy, Chins
AU - Elahinia, Mohammad
N1 - Publisher Copyright:
© 2024 by the authors.
PY - 2024/8
Y1 - 2024/8
N2 - Research into the processability of NiTiHf high-temperature shape memory alloys (HTSMAs) via laser powder bed fusion (LPBF) is limited; nevertheless, these alloys show promise for applications in extreme environments. This study aims to address this limitation by investigating the printability of four NiTiHf alloys with varying Hf content (1, 2, 15, and 20 at. %) to assess their suitability for LPBF applications. Solidification cracking is one of the main limiting factors in LPBF processes, which occurs during the final stage of solidification. To investigate the effect of alloy composition on printability, this study focuses on this defect via a combination of computational modeling and experimental validation. To this end, solidification cracking susceptibility is calculated as Kou’s index and Scheil–Gulliver model, implemented in Thermo-Calc/2022a software. An innovative powder-free experimental method through laser remelting was conducted on bare NiTiHf ingots to validate the parameter impacts of the LPBF process. The result is the processability window with no cracking likelihood under diverse LPBF conditions, including laser power and scan speed. This comprehensive investigation enhances our understanding of the processability challenges and opportunities for NiTiHf HTSMAs in advanced engineering applications.
AB - Research into the processability of NiTiHf high-temperature shape memory alloys (HTSMAs) via laser powder bed fusion (LPBF) is limited; nevertheless, these alloys show promise for applications in extreme environments. This study aims to address this limitation by investigating the printability of four NiTiHf alloys with varying Hf content (1, 2, 15, and 20 at. %) to assess their suitability for LPBF applications. Solidification cracking is one of the main limiting factors in LPBF processes, which occurs during the final stage of solidification. To investigate the effect of alloy composition on printability, this study focuses on this defect via a combination of computational modeling and experimental validation. To this end, solidification cracking susceptibility is calculated as Kou’s index and Scheil–Gulliver model, implemented in Thermo-Calc/2022a software. An innovative powder-free experimental method through laser remelting was conducted on bare NiTiHf ingots to validate the parameter impacts of the LPBF process. The result is the processability window with no cracking likelihood under diverse LPBF conditions, including laser power and scan speed. This comprehensive investigation enhances our understanding of the processability challenges and opportunities for NiTiHf HTSMAs in advanced engineering applications.
KW - computational modeling
KW - high-temperature shape memory alloys (HTSMAs)
KW - laser powder bed fusion (LPBF)
KW - laser remelting experiments
KW - processability assessment
KW - solidification cracking
UR - http://www.scopus.com/inward/record.url?scp=85202430153&partnerID=8YFLogxK
U2 - 10.3390/ma17164150
DO - 10.3390/ma17164150
M3 - Article
AN - SCOPUS:85202430153
SN - 1996-1944
VL - 17
JO - Materials
JF - Materials
IS - 16
M1 - 4150
ER -