Strain behaviour of shock waves loaded titanium nickelide during martensitic transformations

Abstract
Plates of titanium nickelide (Ti-50.5 at. % Ni) rolled in the austenitic B2-state were loaded by shock waves with a pressures of 10 and 50 GPa. Dilatometry and X-ray diffraction show that the shock waves loading led to anisotropic martensitic transformations in the plates. The anisotropy of the transformations is caused by the directional motion of the plate substance in shock waves. The austenitic memory the samples had prior to the loading changed to the martensitic memory, inherent in the martensite deformation. The martensitic memory has not been retained after the reverse martensitic transformation; the samples had remembered the initial state with the austenitic memory. The carriers of the memory are particles of the precipitated phase (Ti ₃Ni ₄) and the dislocation structure formed upon rolling.