Development of thermal boundary condition model at metal/die interface of high pressure die casting process

摘要

A thermal boundary condition model at the metal/die interface of a high pressure die casting process was developed based on two important correlations. The first is the relationship between the maximum interfacial heat transfer coefficient (IHTC) and the initial die surface temperature, and the other is between the IHTC and the casting solid fraction. The IHTC at the metal/die interface during solidification of high pressure die casting process can be divided into four stages, namely, the initial increasing stage, higher value maintaining stage, fast decreasing stage and lower value stage. By applying the regression method, it was found that the maximum heat transfer coefficient during the initial increasing stage changes as a function of the initial die surface temperature, and during the fast decreasing stage, the heat transfer coefficient changes as a function of the casting solid fraction.