Experimental Determination of Interfacial Heat Transfer Coefficient for AZ91E Castings

Summary

There is a sustained interest for the modeling of casting processes. However an accurate simulation of casting processes requires boundary conditions that closely fit the actual process. One of these is the heat transfer coefficient at the mold/metal interface. Unfortunately, no database about the heat transfer coefficient at metal/mold interface is currently available for magnesium alloys. This work, was devoted to the measurement of the temperature dependant heat transfer coefficient at the interface for sand casting. Different casting thicknesses were tested. All experimental specimens were cast using the AZ91E alloy. The temperature was monitored within the casting and the mold during solidification to determine the local cooling curve. Those curves were then used to calculate the heat transfer coefficient at the casting/mold interface as a function of the casting time or temperature at the interface.