A numerical and experimental study of the rate of transformation in three directionally grown peritectic systems

Abstract

Three systems, Ag-Sn, Cu-Sn, and Cd-Ag, with-very-different peritectic phase diagrams, have been investigated. Specimens were directionally grown then quenched. The volume fraction of the two solid phases and the quenched liquid were measured using image analysis of cross sections. A numerical model was developed to calculate the quantity Of the phases as a function of temperature and the results were compared with experiment; It is concluded that the quantities of the different phases can be predicted reasonably well with a: simple diffusion model. The shape of the phase diagram, the size of the primary phase, and the solid-state diffusion coefficients play a crucial role in determining the volume fraction of the final products.