ON THE PARTICLE PUSHING DURING SOLIDIFICATION
凝固过程中的颗粒推斥

Particle pushing is one of the basic problems involved during solid-liquid phase transformation. Classical theory suggested that particle pushing is governed by the surface energy interactions, but this theory could not used to explain particle pushing occurring during the production of some metal-matrix composites. the authors propose that particle pushing is a result of fluid flow that occurs at the front of the solid-liquid interface. Two mechanisms for particle pushing as a result of fluid flow are presented and the criteria for particle pushing are derived. Experiments, carried out to verify the mechanisms and the criteria,show good agreement with theoretical model.