抄録
This study describes the effect of temperature on critical stress for slip of Ti-Ni shape memory alloy. The yield stress of general metals represents the critical stress for slip. However, in shape memory alloy, stress loading causes martensite variant rearrangement in the martensitic phase and stress-induced martensitic phase transformation followed by martensite variant rearrangement in parent phase, so that it is difficult to determine the critical stress for slip of shape memory alloys. Consequently, the critical stress for slip in the mixtures of the martensitic and parent phases has not been clarified yet. To investigate the effect of temperature on critical stress for slip of Ti-Ni shape memory alloy, this study has carried tensile loading-unloading tests using Ti-50.3at%Ni in the temperature range from 193K to 423K. In the temperature range from 273K to 373K, the critical stress for slip in the mixtures of the martensitic and parent phases increases with increasing temperature.
