SPINODAL DECOMPOSITION OF CUCO ALLOYS - A COMPUTER-SIMULATION AND SOME FIM RESULTS

Based on a FIM study of rapidly quenched Cu-50 at% Co alloys, a comput er simulation of the spinodal decomposition of CuCo alloys is carried out applying a numerical version of the Fourier transformation approac h of the nonlinear diffusion equation. A polynomial approach of the fr ee energy function of CuCo solutions is obtained and is applied to the simulations. The simulations show three stages of the evolution of th e composition profile: strong modulation of the wavelength in the earl y stage, growth of the amplitude in the intermediate stage, and regula rization of the configuration and a small recovery effect of the wavel ength in the late stage. The kinetics of spinodal decomposition for di fferent compositions and at different temperatures is also studied in detail. The wavelength of the composition profile shows a weak depende nce on the aging temperature, whereas the kinetics is rapidly accelera ted as the temperature increases.