Superelastic deformation of a TiNi shape memory alloy subjected to various cyclic loadings

摘要

Superelasticity is one of the important mechanical properties of shape memory alloys (SMAs). In the present paper, the superelastic deformation behaviour of a TiNi SMA under various loading conditions with different experimental temperatures and strain rates was investigated. The characteristics of transformation stress during cyclic deformation were analysed. The relationship between the residual stress and strain accumulated during cyclic loading is expressed by a straight line. After mechanical training with cyclic deformation, two-way deformation appears on account of R-phase transformation. The starting and finishing conditions of the transformation become unclear after cyclic deformation at high temperature.