Phase diagram effects in phase field models of dendritic growth in binary alloys

Abstract

Phase field models offer the prospect of being able to perform realistic numerical experiments on dendritic growth in binary alloys. Previous work demonstrated this potential for a nickel-copper system. Simulations were carried out to investigate the effects of varying the grid size, the interface thickness, the noise amplitude and the diffusivity in the solid. In this paper, we investigate phase diagram effects in phase field models. We show how changing various features of the phase diagram changes the length scale and velocity dendritic growth, the degree of solute segregation, and the formation of secondary tertiary dendrite arms. Simulations are based on material parameters for four different binary alloy systems—nickel-copper, gold-silver, antimony-bismuth and aluminium-zinc.