Unified Transformation-Thermoplasticity and the Application
Tatsuo INOUE
Abstract:Most constitutive laws for transformation plasticity, which are known to contribute a drastic effect on the simulation of thermo-mechanical processes, have been treated to be independent of ordinal thermo-plasticity. Considering that the mechanisms for both strains are essentially with no difference from metallurgical viewpoint, the constitutive equation for transformation plastic strain rate is expected to be described in relation with plasticity theory. This paper motivates to derive a unified constitutive model including transformation-induced and ordinal thermo-mechanical plastic strain rates by introducing the effect of varying phases during phase transformation into yield function. Thus derived model is applied to simulate temperature-elongation diagram by use of a kinetic rate equation of induced phase. Key Words:Transformation plasticity, Thermoplasticity, Unified constitutive equation, Transformation plasticity coefficient, Temperature-elongation diagram