AN ANALYTICAL MODEL FOR THE INTERACTION BETWEEN AN INSOLUBLE PARTICLE AND AN ADVANCING SOLID LIQUID INTERFACE

In this article, the behavior of particles in front of an advancing solid/liquid interface was analyzed. In the analytical model presented, the critical velocity for the transition from particle pushing to engulfment by the interface was calculated as a function of relevant material parameters and processing variables. In particular, the effect of the difference in the thermal properties of the particle and the matrix on the particle/interface interaction was examined. It was demonstrated that the presence of particles could destabilize the interface which, in turn, affected the behavior of particles at the interface. Based on the analysis, a particle behavior map was constructed to illustrate the complex particle behaviors in different material systems under various growth conditions. Theoretical predictions were compared against experimental results obtained in transparent organic materials as well as in metallic systems. The relevance of these observations to the melt processing of particulate-reinforced metal matrix composites (MMCs) was discussed.