| Abstract Scope |
Creating a high-quality stainless steel (SS) and aluminium (Al) bimetallic structure has been a challenge due to the formation of brittle Iron (Fe)-Al intermetallic compounds. This study explores the impact of alumina particles doping at the SS-Al interface, revealing insights into melt pool forces and the metallurgical properties. Three SS-Al structures were created using wire arc additive manufacturing (WAAM), with varying alumina content (20, 30, and 40 mg/mm). Alumina decomposition influenced the IMC layer thickness, with oxygen content at the interface increasing with alumina concentration. This affected Marangoni and buoyancy forces, impacting the IMC thickness and grain size. Analyses revealed FeAl, Fe2Al5, and FeAl3 layers, with Fe2Al5 layer thickness increasing with alumina content. The nanometric grain sizes of Fe2Al5 and FeAl3 were observed at the bimetallic interface of lower alumina content found to follow inverse Hall-Petch relationship with hardness. These findings provide valuable data for developing SS-Al structures via WAAM. |