Study on particle pushing in front of growing interface during soldification

Abstract

For in-situ composite materials, the interaction between the second-phase particles and the solidification interface attracts more attentions of people, for concerning the final distribution of the particles on the matrix. With the conception of the local solidification time, a kinematics mechanism of particle pushing into the crystal boundary during the solidification process was assumed. Through the analysis of forces acted on the particle in front of the solid/liquid interface the critical velocity criterion for the particles pushing was given. The calculation results show when the growth rate of the interface V is less than or equals to the critical velocity V c , the particles on the solid/liquid interface is pushed into the boundary region of cellular crystals, where they are distributed as a chain-like straight, which forms a particle-strengthened in-situ composite materials.