| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Powder Materials Processing and Fundamental Understanding
|
| Presentation Title |
Understanding Mechanisms Behind Morphological Changes in Gas Atomized Powders after Laser Irradiation |
| Author(s) |
Jonathan M. Skelton, Connor Headley , Eli Sullivan , James Fitz-Gerald, Jerrold Floro |
| On-Site Speaker (Planned) |
Jonathan M. Skelton |
| Abstract Scope |
This research focuses on morphological changes observed in Al-Cu eutectic alloy powders (1-100μm diameter) irradiated with a CW laser diode (450 nm) on glass substrates. Particles were characterized with scanning electron microscopy before and after irradiation. Changes in the eutectic microstructure clearly demonstrate that melting occurred during laser irradiation, but under these conditions, the particles melted while fully contained within the thin, contiguous native oxide shell. Upon cooling, differential thermal contraction promotes post-buckling instabilities within the shell that severely deform the morphology of the solidified powder particles. The formation of more severe features in smaller particles is surprising, and suggests a dynamic interaction between the moving solidification front and the buckling oxide shell. Similar behavior is seen in Al-Cu eutectic powder particles near the edges of melt tracks in laser powder bed fusion, with implications for powder recycling. Support of the NSF under grant DMR-1663085 is gratefully acknowledged. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Powder Materials, Aluminum, Additive Manufacturing |