Thermo-mechanical analysis of industrial solidification processes

The paper presents an up-to-date nite element numerical model for fully coupled thermo-mechanical problems, focussing in the simulation of solidi cation processes of industrial metal parts. The proposed constitutive model is de ned by a thermo-visco-elasto-(visco)plastic free energy function which includes a contribution for thermal multiphase changes. Mechanical and thermal properties are assumed to be temperature-dependent, and viscous-like strains are introduced to account for the variation of the elastic moduli during the cooling process. The continuous transition between the initial uid-like and the nal solid-like behaviour of the part is modelled by considering separate viscous and elasto-plastic responses as a function of the solid fraction. Thermo-mechanical contact conditions between the mould and the part are speci cally considered, assuming that the heat ux is a function of the normal pressure and the thermal and mechanical gaps. A fractional step method arising from an operator split of the governing equations is used to solve the non-linear coupled system of equations, leading to a staggered product formula solution algorithm suitable for large-scale computations. Representative simulations of industrial solidi cation processes are shown, and comparison of computed results using the proposed model with available experimental data is given