Pseudoelastic hysteresis out of recoverable finite elastoplastic flows

The main objective of this study is to demonstrate that recoverable finite elastoplastic flows are derivable from classical elastoplasticity models and to further establish combined hardening finite image-flow models of this property. With such models, it is shown that every axial strain of a uniaxially loaded bar well beyond the initial yielding is recoverable upon removal of applied load, thus producing a hysteresis loop above the strain axis. It is found that such hysteresis loops of any given shape may be generated by specifying suitable hardening functions. In particular, hardening functions are found to generate flag-like loops associated just with pseudoelastic hysteresis effects of shape memory alloys. This suggests that these effects may be characterized by classical elastoplasticity models from a direct phenomenological standpoint. Explicit, direct results are derived for a general case of multiaxial deformations in a sense of thermodynamic consistency.