|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Additive Manufacturing of Metals: Applications of Solidification Fundamentals
||In situ X-ray Observation and Quantification of Keyhole-induced Porosity during Laser Additive Manufacturing
||Yuze Huang, Chu Lun Alex Leung, Samuel J. Clark, Siu Lun Yeung, Yunhui Chen, Lorna Sinclair, Sebastian Marussi, Kamel Fezzaa, Jeyarajan Thiyagalingam, Peter D. Lee
|On-Site Speaker (Planned)
High-speed synchrotron X-ray imaging during laser additive manufacturing was used to quantify the evolution of keyhole porosity for a range of processing conditions in pure aluminum and alloy 7A77. The real-time changes in keyhole and pore size and morphology were quantitatively characterized. Statistical analysis was performed to correlate the in-situ dynamics between keyhole and pores. It was found that the radial fluctuation of keyhole plays a more significant effect on pore formation than that of axial oscillation. Using these new insights, a pore growth model accounting for vapor condensation, hydrogen diffusion, and argon content as a function of the local thermal and pressure variations was derived, quantitatively predicting keyhole pore evolution. The model was validated against pore characteristics (e.g. equivalent diameter) for a range of different laser velocities. These results both provide new insights into pore formation and evolution during laser manufacturing processes such as additive manufacturing and welding.