A uniaxial model for shape-memory alloys

We present a uniaxial model for shape memory alloys, cast within the generalized plasticity framework, previously developed. The model is based on two internal variables (the single-variant martensite fraction and the multiple-variant martensite fraction), for which evolution equations in rate form are proposed. The model reproduces the shape-memory effect and the superelastic behavior; moreover, for loading-unloading cycles, without completion of the phase transition, it presents a cyclic response with internal loops. (C) 1997 Elsevier Science Ltd.