An experimental investigation on rate dependency of thermomechanical and Stress-induced martensitic transformation behavior in Fe-28Mn-6Si-5Cr shape memory alloy under compression

Abstract

For the great potential Fe-Mn-Si shape memory alloy (Fe-SMA), which is less expensive compared with the Ni-Ti system, tension-compression asymmetry in stress-strain curve is reported in the past. It is considered that the difference in thermomechanical and stress-induced martensitic transformation behavior may also be observed under different loading modes in Fe-SMA. In this paper, an experimental investigation under compression is conducted to make clear the rate dependency of thermomechanical and phase transformation behavior in Fe-SMA at the previous study focusing on the behavior under tension. During both quasi-static and impact compression, the amount of stress-induced ε-martensite can be indirectly evaluated by using a real-time measurement method of an electrical resistance. Furthermore, temperature change which becomes an important aspect of the study on the phase transition is also captured. In addition, after compressive test and heating, it is attempted to investigate the rate dependency of volume fraction of stress-induced ε-martensite and shape recovery strain. Finally, the microstructural observation of the samples taken from the specimen is carried out.