| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing: Materials Design and Alloy Development III -- Super Materials and Extreme Environments
|
| Presentation Title |
The Mechanisms Behind the Effect of Oxygen on DED AM Ti Alloy Build |
| Author(s) |
Caterina Iantaffi, Yunhui Chen, Samuel J. Clark, Robert C. Atwood, Eral Bele, Martina Meisnar , Thomas Rohr , Lertthanasarn Jedsada, Minh-Son Pham, Peter D. Lee |
| On-Site Speaker (Planned) |
Caterina Iantaffi |
| Abstract Scope |
To prevent oxygen contamination, Laser Additive Manufacturing (LAM) techniques are normally operated in an inert gas chamber. An alternative method, useful for large builds and component reparation, is the application of a localised inert gas shield. We investigate the effect of oxygen contamination on Ti6242 during directed energy deposition (DED) additive manufacturing using an inert gas chamber compared to a gas shield. It has been discovered that, in gas shield mode, the amount of oxygen absorbed from the atmosphere was sufficient to reverse the Marangoni flow leading to an alteration of the molten pool morphology, strongly affecting porosity formation. Furthermore, the high oxygen level resulted in the precipitation of primary α phase, and refined the grain structure. The commonly developed Widmanstätten microstructure was completely suppressed. The presented results elucidate the influence of oxygen contamination in additively manufactured Ti alloys, and help identify improved industrial practises for titanium additive manufacturing. |
| Proceedings Inclusion? |
Planned: |