Abstract: FEM equation of the transient heat conduction problem is deduced with the Galerkin Method. Through the discussion on the energy conservation condition of FEM schemes, a conservative FEM model of transient thermal field of casting processing is presented in which side length of the triangular element is taken as weighting factor for the lumped capacitance mateix. To taken account of the latent heat release during the solidification of castings accuratly, the latent curve of low carbon steel was measured experimentally based on the principle of DTA and an effective iteration technique of the latent heat treatment was developed by means of the picking-up method. The computation results show that the model is reliable, adaptable, more accurate and with higher computing speed.

Key words: FEM model, Solidification of casting, Thermal field