Thermodynamic Consistency of Two-mechanism Models in the Non-isothermal Case

Abstract

This note investigates two-mechanism models (= 2M models) in the case of plastic behavior. 2M models (or, generally, multi-mechanism models) are a useful tool for modelling of complex material behavior. They have been studied and applied for the last twenty years. We prove thermodynamic consistency for some classes of 2M models, and we derive new coupled evolution equations for the back stresses. Moreover, a coupling in the evolution equations of the internal variables is presented. Finally, a comparison between a 2M model and a modified Chaboche
model is presented in order to illustrate the possibilities and problems in modelling of complex material behavior like ratcheting.