Analytical and Experimental Research on Pseudoelastic Behavior of Shape Memory Alloys under Biaxial Loading

摘要

We suggest an analytical model that can simulate the pseudoelastic behavior of an SMA circular rod under tension-torsion combined loading. To describe the material behavior at the transformation region, we used Brinson's martensite transformation kinetics, as well as the plastic flow rule. The boundary layer of the elastic region and the transformation region were assumed to monotonically decrease from the outer radius, and the thermal expansion effect was not considered. We also present some numerical solutions of the constitutive model and experimental results in the context of isothermal strain and stress processes (for proportional loading). The measured load-strain response in the tension-torsion combined loading experiment is well approximated by the predictions from the constitutive equations.