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Title: Microstructure, Mechanical Properties and Oxidation Behavior of Refractory Multi-principal Element Alloys by Laser Remelting and Conventional Manufacturing
Refractory multi-principal element alloys (RMPEAs), HfNbTaTiZr, (HfNbTaTiZr)9Cr and (HfNbTaTiZr)9Al, were manufactured using vacuum arc melting followed by laser-remelting to mimic additive manufacturing. The microhardness of as-cast HfNbTaTiZr, (HfNbTaTiZr)9Cr and (HfNbTaTiZr)9Al samples after arc melting was measured as 6.20, 7.63 and 6.89 GPa, respectively. After laser-remelting and re-solidification, the hardness increased by ~30% for each composition; the hardest was (HfNbTaTiZr)9Cr measured at 9.60 GPa, and the softest was HfNbTaTiZr with a hardness of 8.42 GPa, which was still harder compared to all the as-cast samples. The addition of Al and Cr led to enhanced oxidation resistance for the respective RMPEA systems. The Al-containing composition showed the best oxidation resistance for the as-cast samples; however, after laser remelting, the Cr-containing RMPEA had the best overall oxidation resistance, and the increase in weight after oxidation dropped by 42% when compared to that for the as-cast alloy. Laser remelting the RMPEAs led to an improvement in mechanical properties; it also resulted in enhanced oxidation resistance for (HfNbTaTiZr)9Cr. However, laser remelting barely changed the oxidation resistance for (HfNbTaTiZr)9Al, and it decreased the oxidation resistance for HfNbTaTiZr. These phenomena are related to microstructure changes induced by the laser remelting/additive manufacturing as compared to conventional casting-based manufacturing.  more » « less
Award ID(s):
2207965
PAR ID:
10519052
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
JOM
Volume:
75
Issue:
12
ISSN:
1047-4838
Page Range / eLocation ID:
5055 to 5065
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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