About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Additive Manufacturing of Metals: Applications of Solidification Fundamentals
|
Presentation Title |
Pore Dynamics and Formation Mechanisms during Directed Energy Deposition Additive Manufacturing |
Author(s) |
Kai Zhang, Yunhui Chen, Xianqiang Fan, Sebastian Marussi, Imogen Cowley, Maureen Fitzpatrick, Shishira Bhagavath, 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, detrimental to the mechanical performance of manufactured components. In this study, we utilised high-speed in situ synchrotron X-ray imaging to observe the pore dynamics and pore formation mechanisms. We revealed three pore behaviors and their formation mechanisms: (i) large pores are formed by pore coalescence; (ii) pores are being pushed in the melt pool by the Marangoni flow, while large pores escape periodically once they reach a critical pore size; (iii) the majority of the pores form from melting of gas atomized powders rather than previously built layers. The pore dynamics and formation mechanisms discovered here can guide to develop porosity elimination strategy in industrial practice. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Powder Materials, Solidification |