Strain-hardening behaviors of TRIP-assisted steels during plastic deformation

On the basis of a continuum mechanical theory, a micromechanical model calculating strain-hardening exponent for TRIP-assisted steels is proposed, in which both contribution of the individual phases and that of interaction between constituent phases to the overall hardenabilty is considered. And TRIP effect is introduced by regarding the volume fraction of retained austenites as a function of plastic strain. Uniaxial tensile and SEM monitor of the microstructures in different strain levels have been used to help understand strain-hardening behaviors. It could be concluded that strain-hardening exponent is a variable of plastic strain and fluctuates along a parabolic path instead of constant during the whole deformation.