Abstract
In order to reveal the mechanism of negative rate-sensitivity in tensile deformation behavior of Fe-28Mn-6Si-5Cr shape memory alloy, the forward and reverse transformation kinetics models has already been proposed. The sensitivity can be modelled by not only direct-introduction of strain rate into the model but also introduction of temperature change depending on the strain rate. Then, only the forward kinetics model is focused upon and the heat conduction equation is derived based on the weak formulation to include the heat transfer boundary condition. However, the identification of the parameter in the past-proposed forward kinetics model is insufficient to express the experimental results. According to the experimental results, temperature rises and stress decreases nonlinearly during unloading. These features cannot be expressed by the past-proposed reverse kinetics model. In this study, a reverse kinetics model is newly-proposed to reflect the modifications of the forward kinetics model. In addition, the identification of the parameters for the forward kinetics model is improved.
