Abstract
Die casting shrinks due to decrease of volume through the solidification process in mushy state and the following cooling process in solid. As the die set prevents die casting from shirking freely, high thermal stress occurs inside it and sometimes breaks products. Die casting also deforms largely when it is pulled out from die set. In the paper the effect of ununiform temperature distribution, shrinkage of volume and the shape of die set on stress distribution and deformation of die casting during solidification and cooling process is investigated by FEM computer simulation about two typical shapes of products, a cylindrical model with a large step between thick and thin wall and a square model with thin wall and narrow rib at the rim like a case of Mini-Disc player. Especially the analysis on thermal stress in sand casting in which the restriction of deformation is very small is carried out about a same cylindrical model.
