Dissolution kinetics of primary silicon in hypereutectic Al–Si melt

The dissolution process of primary silicon particles in Al-18%wt silicon alloy was studied both bya melt overheating experiment and by theoretical analysis. A dissolution model of primary silicon in the melt was established based on atomic diffusion and taking account to interface reaction and curvature of particles. The results show that the theoretical curve agrees with the experimental curve at an overheating temperature of 1100ºC. However, there was some deviation at 700ºCdue to retained silicon clusters in the melt at lower temperature. Therefore, the model is in accord with experiment whennot considering the influence of retained silicon clusters.