Thermo - viscoplastic Constitutive Model of Metallic Materials under High Strain Rates

摘要

A constitutive model considering the effects of strain hardening, strain rate hardening, thermal softening and material damage is suggested. In order to take the effect of material damage into account, a strain softening term is added in Johnson-Cook flow stress law. The model can predict the overall deformation process of metallic materials at high strain rates. And a simple way is provided to determine the coefficients of softening term.