Finite element calculation of B2–B19 transformation of TiNiCu shape memory alloy

This paper presents a three-dimensional calculation model for martensitic transformation and the numerical results were compared with experimental load-biased thermal cycling data of Ti–35Ni–15Cu (at%) shape memory alloy. Our new model accounts for the self-accommodation part of the variants separately in addition to the conventional individual variants. Thermodynamic driving force for a transformation between bistable states was provided in terms of a potential energy of each variant. Transformation kinetic parameters were applied differentially to the self-accommodation and the individual variants. By this approach, interplay between thermodynamics and kinetics of the self-accommodation and the individual variants could be successfully captured. The model has predicted the experimental result more accurately than the model without the self-accommodation part.

► We conduct finite element analysis of shape memory alloy. ► Bistable Arrhenius type equation is used. ► 6 correspondence variants and one self-accommodation variant are considered. ► Load-biased thermal cycling test of Ti–Ni–Cu alloy is considered. ► Experimental result in the literature is more accurately predicted by our model.