Multiscale Modeling of Particle-Solidification Front Dynamics, Part 3: Theoretical Aspects and Parametric Study (Preprint)

摘要

The development of the solidified microstructure in metal-matrix composites depends on complex interactions between non-planar solidification fronts and multiple particles. The problem is multiscale in nature; the motion of the particle (under the action of a nano-scale disjoining pressure force and a micro-scale viscous drag force) is dynamically coupled with the developing solidification front morphology, which is dependent on a variety of thermal conditions. Using computational techniques discussed in parts I and II, this paper seeks to describe the complicated nonlinear parametric dependencies of the phenomenon. The effects of four of the most important parameters in the particle-solidification front interaction are investigated, i.e. the Hamaker constant, the particle size, the thermal conductivity ratio of the particle to the melt, and the solid-liquid interfacial free energy. By performing simulations using the multiscale approach the dependencies of the critical velocity on these four parameters is clarified.