Influence of Strain Rate on Stress–Strain Response of Ni–Mn–Ga Ferromagnetic Shape Memory Alloy Single Crystals

Abstract

Stress–strain behaviors of Ni–Mn–Ga single crystals were characterized by measurement of stress-induced martensite reorientation under constant magnetic fields. For this purpose, a new setup was designed and manufactured. This setup was supplemented to Santam STM-50 compression testing machine to carry out compression tests, while the specimen was subjected to a constant magnetic field. All the experiments were performed at room temperature in which the sample was at martensite phase. The results indicate that strain rate has no significant effect on stress–strain response of the specimen for strain rates less than 2 × 10−2 s−1 at complete and incomplete loading–unloading cycles.