Twin boundary motion in NiMnGa single crystals under biaxial compression

Martensite reorientation via twin boundary motion in NiMnGa single crystals was experimentally studied under biaxial loadings. The threshold driving force (related to the energy dissipation) of the twin boundary motion, and the transformation strain due to martensite reorientation are found to be constant in all tested 2D stress states. These findings imply that the materials can work at high levels of multi-axial stresses while keeping their advantages — low intrinsic dissipation and large reversible strain.