Comprehensive Modeling Of Finite Strain Pseudoelastic Alloys Up To Failure

An explicit,finite strain elasto-plastic constitutive model with thermodynamic consistency is proposed to achieve a comprehensive simulation of inelastic behaviors of shape memory alloys(SMAs) within the pseudo-elastic range, including initial plastic stage with small elasto-plastic strain,pseudo-elastic stage with perfect strain recovery, hardening stage with partial strain recovery, and softening stage up to failure. The tension-compression asymmetry at the pseudo-elastic stage is taken into consideration. A new, explicit methodology based on any given uniaxial data is introduced to obtain multi-axial expressions for the hardening moduli and the stress strength incorporated in this model, in such a unified sense that all four successive deformation stages may be simultaneously represented. As compared with existing models, the new model display novelties in three respects: 1. it bypasses usual complicated procedures dealing with both the microscopic mechanism of martensite-to-austenite transition and the micro-to-macro connection; 2. it can simultaneously simulate hysteresis loops, plastic deformation and softening up to failure; and 3. it is of wide applicability to all kinds of SMAs.