About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
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Additive Manufacturing, Directed Energy Deposition of Metals: Processing – Microstructure – Mechanical Property Relationships
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| Presentation Title |
Investigation of Micro-Cracks in Additively Manufactured TiAl via EBSD. |
| Author(s) |
Collin Pickersgill, Zhaoying Ding, Chenwei Shao, Yu Zou |
| On-Site Speaker (Planned) |
Collin Pickersgill |
| Abstract Scope |
Titanium aluminide alloys are a material of interest for many lightweight, high temperature structural applications. Fabrication of these alloys with additive manufacturing provides routes for design customization in complex shapes and with efficient source material use but requires ongoing characterization and testing to develop the maturity of the technology. Following optical microscopy and EBSD testing of the intermetallic Ti-48Al-2Nb-2Cr alloy fabricated with L-DED, microcracking within and between grain structures can be attributed to melt pool thermal stresses during the printing process. These stresses form cracks favorably in grains with brittle slip systems in relation to directions of planar stress. Our findings culminate in a novel and thorough cracking mechanism, in which the role
of the thermal gradient directions, granular crystallographic orientation, and constituent phase structure are addressed as contributors. This work informs the approach toward fabricating defect-free parts with superior mechanical integrity. |