Investigation of Shape Recovery Characteristics on Ferrous Shape Memory Alloy
Aims of this study are to clarify the shape recovery characteristics on ferrous shape memory alloy in order to utilize one as a many kinds of mechanical components. In this study, Fe-Mn-Si-Cr shape memory alloy is used. The fundamental characteristics and the shape recovery characteristics are investigated in this alloy. From the result of this investigation, shape recovery strain without training process reaches to maximum value of 2% at the amount of 5∼7% work-strain. That with the training process reaches 3.5% in the maximum, which is 1.8 times of that without training process. In addition, the shape recovery characteristic under constant stress which is given during the heating process is investigated. The microstructure of the deformed material is observed. The Widmanstatten structure is generated. This structure is attributed to the transformation from austenite to ε-martensite. In order to enable the prediction analysis of the shape recovery behavior, the relationship between shape recovery strain and work-strain is formulated by the regression analysis in cubic equation.