Synthesis and characterization of Fe-Mn-Si shape memory alloy by mechanical alloying and subsequent sintering

An Fe-Mn-Si bulk alloy was produced from elemental powders by mechanical alloying (MA) and subsequent sintering. The shape memory effect, microstructure and mechanical property of the bulk alloy were investigated. The α phase transformed into the γ phase during MA. The MA played an essential role in stabilizing the γ phase, which is associated with the shape memory effect in this alloy system. The γ phase with small amounts of ε and α' martensitic phases formed after subsequent sintering. After deformation, a γ→ε stress-induced martensitic phase transformation occurred. Shape recovery was observed after subsequent heating, associated with an ε→γ reverse martensitic transformation. The grain size of the bulk alloy was about 2-3. μm, and the yield strength was about 500. MPa. These results show that powder metallurgy, a combination of MA and subsequent sintering, has the potential to produce Fe-Mn-Si shape memory alloy.