A MICRO-SEGREGATION MODEL

摘要

In this paper a micro-segregation model, on the scale of a dendrite secondary arm space, is developed. The model is constructed to interface with macro-scale solidification calculations of multi-component alloys and account for coarsening effects. The keys step in the model is a discrete time stepping that allows for the application of equilibrium (lever rule) thermodynamics, applied to the solid fraction that forms in a given time step, without compromising the overall non-equilibrium solid solute distribution. The application of the model is illustrated by comparing its predictive performance, for several limit cases, with analytical and full numerical micro-segregation solutions.