About this Abstract |
| Meeting |
TMS Specialty Congress 2026
|
| Symposium
|
4th World Congress on High Entropy Alloys (HEA 2026)
|
| Presentation Title |
Process-Structure Relationships in Additively Manufactured MoNbTaTi Refractory HEA |
| Author(s) |
Erin Barrick, Ping Lu, Paul Specht, Andrew Polonsky, Levi Van Bastian |
| On-Site Speaker (Planned) |
Erin Barrick |
| Abstract Scope |
Additive manufacturing (AM) is appealing for rapid alloy development of refractory HEAs (RHEAs) as well as potential full-scale processing. Equiatomic MoNbTaTi was fabricated with blown powder laser directed energy deposition (L-DED) using elemental powder feedstock. Initial challenges with full melting and uniform chemistry ascribed to disparities in melting temperature and other thermophysical properties prompted the integration of a laser remelting strategy to improve print quality. Novel metallographic etching techniques enabled observation/measurement of individual melt tracks to rationalize the effects of processing on print quality and microstructure. Grain boundary cracks observed after printing were characterized using scanning transmission electron microscopy (S/TEM) to understand the cracking mechanism(s). The techniques developed in this work are adaptable to other RHEAs to enable successful printing with elemental powders and have implications for full-scale adaptation with regards to compositional control and impurity elements. SNL is managed and operated by NTESS under DOE NNSA contract DE-NA0003525 |
| Proceedings Inclusion? |
Undecided |