|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Additive Manufacturing for Energy Applications III
||On the In-situ Formation of Nano Oxides during Laser Powder Bed Fusion as a Function of Steel Chemistry and Atmospheric Oxygen Level
||Houshang Yin, Pu Deng, Miao Song, Mallikarjun Karadge, Xiaoyuan Lou
|On-Site Speaker (Planned)
Efforts have been made to understand the origins of in-situ nano-oxide formation during laser powder bed fusion (LPBF). This work aims to obtain insights into the oxidation pathway and nano-oxide dispersion during LPBF to support the efficient production of oxide dispersion strengthened (ODS) alloys by laser additive manufacturing (AM). Three austenitic stainless steels alloyed with different elements (have different oxygen affinity), Y, Al, and Si respectively, were used for fabrication in AM machine with varied atmospheric oxygen levels and laser parameters. The oxidations of spattered powders and melt pool surface were identified as main contributors to oxygen intrusion. The amount, size, distribution of the oxide in AM stainless steel were found sensitive to the type of oxygen getter, alloying concentration, and energy input. Depending on the alloying elements, post-process heat treatment can influence the evolution of the nano-oxides, which was revealed by oxide characterization and micro/nanoindentation.