Modelling Steady State Deformation in Metals by a Novel Themostatistical Approach

摘要

A novel model based on linear non-equilibrium thermodynamics and statistical mechanics to describe the microstructure evolution during steady state deformation in metals is presented. Steady state is treated as a stationary non-equilibrium state in the framework of linear non-equilibrium thermodynamics. It is modelled by equating the entropy production inside the bulk to the entropy flow towards the surroundings, so that total entropy remains constant. Based on this assumption, the saturation flow stress, dislocation density and subgrain size are computed as a function of temperature and strain rate. The model is applied to pure Al, Cu, Ni, and Ag showing good agreement with experimental results.