Homogenization of multicomponent alloys via partial melting

A practically important case, when homogenization of multicomponent alloys is achieved through partial melting, is analyzed. In the course of this pro cess, liquid pools, initially formed from interdendritic material after re- heating, shrink continuously, change their composition, and finally disappe ar to leave an inhomogeneous solid solution behind. To tackle this diffusio n-controlled isothermal process, a comprehensive mathematical model was dev eloped to couple thermodynamic properties and kinetic characteristics. In p articular, a numerical solution of the transient liquid phase problem for t he multicomponent case is presented. The model was applied to simulate homogenization processes in Cu-Ni-Sn comm ercial alloys. Since the validity of quantitative estimations and predictio ns obtained with this model depend on the reliability of input thermodynami c information, the properties of the liquid and FCC phases in the Ni-Sn and Cu-Ni-Sn systems were re-assessed using the CALPHAD method.