About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
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Symposium
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Additive Manufacturing: Advanced Characterization with Synchrotron, Neutron, and In Situ Laboratory-scale Techniques III
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Presentation Title |
Controlling Bubble Dynamics Mechanisms during Directed Energy Deposition Additive Manufacturing |
Author(s) |
Kai Zhang, Shishira Bhagavath, Sebastian Marussi, Imogen Cowley, Xianqiang Fan, Harry Chapman, Alexander Rack, Martyn Jones, Chu Lun Alex Leung, Peter D. Lee |
On-Site Speaker (Planned) |
Kai Zhang |
Abstract Scope |
Directed energy deposition (DED) is a promising laser additive manufacturing technique to build large components and for repair applications. Porosity can limit the industrialisation of the DED process, reducing end component mechanical performance. In this study, we use high-speed in situ synchrotron X-ray imaging to reveal the bubble evolution mechanisms and demonstrate a novel in situ strategy to control the bubble dynamics. Bubble evolution mechanisms include bubble formation, coalescence, growth and entrapment. We found that bubbles are primarily formed from argon pores in the gas atomized powder feedstock. These small bubbles coalesce to form large bubbles. We demonstrate the bubble dynamics can be controlled by laser power, build velocity and the addition of particles, all of which alter the melt pool dynamics. The bubble evolution and controlling mechanisms discovered here can guide to develop a more effective porosity elimination strategy in industrial practice. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Characterization, Solidification |