Constitutive Equation for the Hot Deformation Behavior of TiNiNb Shape Memory Alloy

In this research , hot deformation behavior of NiTiNb alloy was explored. Then, the activation energy and the constitutive equation were evaluated and obtained. The results show that the compressive process of TiNiNb alloy is a typical rheological process. The thermal activation energy of TiNiNb alloy in the temperature range of 720–840°C is 198.004 kJ/mol. Both NiTi matrix phase and Nb solution have been refined. The amounts of (Ti, Nb) 2 Ni hard brittle phase and Nb solution were gradually reduced with increasing the strain rate and deformation temperature.