| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Defects and Properties of Cast Metals
|
| Presentation Title |
Resolving Pore Evolution Mechanisms During Laser Powder Bed Fusion Additive Manufacturing by Multi-modal Imaging |
| Author(s) |
Chu Lun Alex Leung, Sebastian Marussi, Lorna Sinclair, Samuel Clark, Yunhui Chen, Leigh Stanger, Jon Willmott, Robert C Atwood, Andrew J Bodey, Margie P Olbinado, Alexander Rack, Peter D Lee |
| On-Site Speaker (Planned) |
Chu Lun Alex Leung |
| Abstract Scope |
Pore evolution mechanisms in laser powder bed fusion (LPBF) additive manufacturing depend on many factors, ranging from materials chemistry to processing parameters, and hence are not well-understood. Here, we capture the pore dynamics inside single-layer melt tracks during PBF of virgin and oxidised powders using high-speed synchrotron X-ray, optical, and infra-red imaging. This is done for both overhang and multi-layer build conditions. Our results show that pores can form during melting and during solidification. Gas pores can (1) migrate in the molten pool via Marangoni convection, (2) grow in the expense of the others via coalescence, (3) dissolve into the solid solution or (4) eject as spatter during laser re-melting, (5) and precipitate into the melt pool or (6) lead to bubble bursting during cooling. Our results confirm that their size, morphology, and location are strongly depending on the processing parameters, shedding light onto pore formation mechanisms in LPBF. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |