A three-dimensional numerical model for a convection-diffusion phase change process during laser melting of ceramic materials

Using a fixed-grid source-based method, a three-dimensional numerical model for a convection-diffusion phase change process during laser melting of ceramic materials has been studied. The model was applied to a realistic binary phase diagram containing a eutectic composition, including both an isothermal phase change occurring at a distinct temperature and a phase change taking place over a temperature range (the mushy region phase change). The effects of latent heat of fusion and fluid flow in the melt pool on the temperature, velocity fields and shape of the melt pool were analysed and compared. Results indicated that the effects of latent heat of fusion were more significant than those of fluid flow for two simulation cases, considered in the model. The best prediction accuracy for the profiles of the melt/ solid interfaces was achieved from the developed model by considering both the latent heat of fusion and fluid flow in the melt pool. (C) 2004 Elsevier Ltd. All rights reserved.