Heat transfer at the casting/die interface in high pressure die casting : experimental results and contribution to modelling

The present paper deals with a new measurement method to determine the heat transfer coefficient and the heat flux density at the interface between a casting and its die. This method and the related Heat Transfer Gauge were developed together as a cooperative project between CAST (Australia) and CROMeP (France). The device enables the determination of the heat transfer coefficient in an industrial casting machine. Several campaigns with High Pressure Die Casting machines and Gravity Die Casting machine have already taken place in Australia and in Europe, both in research laboratories and on commercially-run casting machines. In this paper we present results from a measurement campaign with a thoroughly instrumented HPDC die machine located at CSIRO in Melbourne. The influence of piston velocity, intensification pressure and various other process parameters on the heat transfer are studied. A model is being developed to explain the evolution of thermal resistance at the casting/die interface, before the formation of a complete air gap. Its first stages are explained here.