Energy Dissipation of Martensite Reorientation in NiMnGa Single Crystals under Biaxial Compression

Abstract

Experiments of biaxial compression were conducted to study the energy dissipation (stress-hysteresis) of martensite reorientation in NiMnGa single crystals. From the experiments, the observed stress-hysteresis consists of two parts ― the material intrinsic friction due to martensite reorientation, and the external friction between the loading clampers and the sample surfaces. It is found that the former one is independent of the 2D stress state while the latter one strongly depends on the 2D stress levels. Both kinds of friction are important and need to be considered in real applications.