Numerical simulation of peritectic reaction using a multi-phase-field model

A multi-phase-field model is applied to simulate the peritectic reaction of Fe-C alloys. The phase-field equations, the diffusion equation for the multi-phase-field model and a dilute solution approximation for the descriptions of the free energy densities are presented. The thin-interface limit of the phase-field model for alloy solidification is employed to obtain the parameters relationship. The calculated results of the peritectic reactions show that the growth rates of the gamma phase follow the parabolic growth kinetics in 1-D isothermal transformations and the linear growth kinetics in the 1-D continuous cooling case. During the 2-D peritectic reaction, where liquid, delta and gamma phase are in mutual contact, the moving directions of interface are in accord with the driving force of the phase transformation at the interfaces.