A thermomechanical model for the analysis of light alloy solidification in a composite mould

Acoupled thermomechanical model to simulate light alloy solidi_cation problems in permanent composite moulds is presented[ This model is based on a general isotropic thermoelasto!plasticity theory and considers the di}erent thermomechanical behaviours of each component of the mould as well as those of the solidifying material during its evolution from liquid to solid[ To this end\ plastic evolution equations\ a phase!change variable and a speci_c free energy function are proposed in order to derive temperature!dependent material constitutive laws[ The corresponding _nite element formulation and the staggered scheme used to solve the coupled non! linear system of equations are also presented[ Finally\ the temperature and displacement predictions of the model are validated with laboratory measurements obtained during an experimental trial