Original paper(Vol.53 No.12 pp.1365)

Macroscopic Constitutive Modeling of TRIP Steel Using Green Function and Computational Simulation of Its Deformation Behavior

Takeshi IWAMOTO, Toshiyuki SAWA and Masahiro SASAKI

Abstract:TRIP steels possess such favorable mechanical properties as high work-hardening characteristics, tenacity and strength due to strain-induced martensitic transformation during plastic deformation. However, appropriate mechanical properties are realized under quite restricted circumstances. To obtain the expected mechanical properties, more precise modeling of deformation behavior of TRIP steel is indispensable. Therefore, the constitutive equation for TRIP steel should be established based on micromechanics. Here, based on the Green function and self-consistent approximation for homogenization, a strain rate field in the microregion and a macroscopic constitutive equation for TRIP steels are derived. Then, the tensile test of the plane strain block of SUS304 is simulated by FEM along with the proposed constitutive equation. Finally, the effects of the geometrical characterisitics of matensite particles on its mechanical properties are discussed.

Key Words:Micromechanical model, TRIP steels, Strain-induced martensitic transformation, Green function, Self-consistent approximation, Geometrical characteristics of martensitic particles, Mechanical properties