Multi-phase-field simulation of austenite peritectic solidification based on a ferrite grain* *Project supported by the Science Challenge Project, China (Grant No. TZZT2019-D1-03), the National Natural Science Foundation of China (Grant No. 51972028), and the National Key Research and Development Program of China (Grant No. 2019YFA0307900).

Abstract

A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.