金属材料在高应变率下的热粘塑性本构模型

A THERMO-VISCOPLASTIC CONSTITUTIVE MODEL OF METALLIC MATERIALS AT HIGH STRAIN RATES

提出了一种考虑应变强化、应变率强化、热软化效应及材料损伤的本构模型 ,通过在Johnson Cook热粘塑性本构关系中增加一个随应变增大应力减速小的软化项 ,反映材料的损伤 .该模型可以很好地预测材料的整个变形过程 。

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