About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Additive Manufacturing: Materials Design and Alloy Development V – Design Fundamentals
|
Presentation Title |
Suppressing Large Columnar Grain Structures in Ti Alloys Processed with Laser Wire Directed Energy Deposition |
Author(s) |
Alexander R. Hansen, Emma Vetland, John Potter, Chad Henry, Jonah Klemm-Toole, Zhenzhen Yu |
On-Site Speaker (Planned) |
Alexander R. Hansen |
Abstract Scope |
Many titanium alloys processed with additive manufacturing suffer from anisotropy due to the formation of highly textured, large, columnar grains caused by large thermal gradients during solidification. In this study, large columnar grains were suppressed through the addition of alloying elements with high growth restriction factors, increasing the compositional undercooling of the alloy system, and inoculants, acting as heterogeneous nucleation sites. Utilizing powder core wires, novel compositions of alpha-beta and near beta titanium alloys were developed; their as-deposited microstructures were analyzed and compared to a Ti-6Al-4V control deposition. The compositions studied are categorized as having high or low growth restriction and high or low nucleation potential. A columnar to equiaxed transition model was developed for each composition to determine the potential to suppress large columnar grains. As-solidified grain size and morphology comparisons were made by reconstructing prior beta grains, revealing a measurable impact on size and morphology. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Titanium, Other |