Casting shells in permanent moulds

Abstract

Computer simulation of the solidification process is used widely in industry in the design of the mould and the die configuration. The heat-transfer coefficient between the mould and the cast metal is one of the important variables. In this work, the heat-transfer behavior and the time-dependent heat-transfer coefficient between an iron casting and a metallic mould were investigated by inverse heat-conduction analysis. A one-dimensional inverse heat calculation program, which can be used in both rectangular and cylindrical coordinate systems, was developed based on a non-linear estimation method. Temperature distributions along the direction of heat flux from the casting to the mould were measured, the predicted temperature profile being found to compare well with the experimental results. The heat-transfer coefficient was found to drop rapidly during the initial stage of solidification and then increase with the solidification process after a short time period of steady stage. It is concluded that a three stage segmented linear equation of the coefficient can be used to represent the heat-transfer behavior and be implemented in numerical analysis of the casting process.