A Shape Memory Alloy Constitutive Model with Polynomial Phase Transformation Kinetics

Shape memory alloys (SMAs) have a complex thermomechanical behavior due to the variety of strong nonlinear phenomena involved. In this regard, the SMA constitutive modeling is still a challenging topic even after several relevant research efforts related to that. Among these possibilities, there is a class of constitutive model that assumes the phase transformation kinetics, combining simplicity with good results. This work proposes a novel constitutive model with polynomial phase transformation kinetics where the main advantage is to explicitly evaluate either stress-driven or strain-driven cases avoiding iterative algorithms. This approach is of special interest for several situations, including dynamical applications and finite element analysis. Numerical simulations are carried out showing the model capabilities to describe the thermomechanical behavior of SMAs. Initially, the model is compared with quasi-static experimental tests showing a good agreement. Afterward, dynamical analysis is developed considering a single-degree of freedom oscillator indicating the model ability to capture the main features of the SMA nonlinear dynamics .

Automated summary

Shape memory alloys (SMAs) have complex thermomechanical behavior due to various nonlinear phenomena. This study proposes a novel constitutive model with polynomial phase transformation kinetics, which can explicitly evaluate stress-driven or strain-driven cases without iterative algorithms. The model is validated through experimental tests and numerical simulations, showing its capability to accurately describe the thermomechanical behavior of SMAs.