A continuous Masing approach for a physically motivated formulation of temperature and strain-rate dependent plasticity

摘要

This study proposes a physically motivated continuous Masing-type model able to accurately describe the temperature and strain-rate dependent elastic-plastic behaviour of a low alloy steel. A modified Cauchy formulation for the element yield strain distribution function is presented that describes a continuous elastic-plastic transition on the basis of four physically interpretable and easily determinable parameters. The performance of the model is compared to conventional strain-hardening models as well as to monotonic and loading-unloading experiments. Furthermore, the description of monotonic temperature and strain-rate dependent constitutive behaviour of a bainitic 2CrMoNiWV steam turbine rotor steel is evaluated on the basis of experimental data. The proposed model represents very well the elastic-plastic constitutive behaviour of 2CrMoNiWV and allows for an adequate extrapolation from a restricted experimentally covered regime. It is believed to form a promising basis for the development of plasticity model formulations.