2003 Volume 75 Issue 10 Pages 682-687
This work aimed to predict and prevent porosity defects occurring in a tire-mold aluminum casting using integrated numerical simulations of solidification and mold filling. First, the numerical results of solidification simulation and conventional porosity prediction methods indicated that solidification contraction and sequence were probably not the reason for the porosities. Before judging whether the porosities were flow-related, simulated results were evaluated by comparing with the observed results of water-simulation experiments and real castings. It was found that inlet boundary conditions adopted in calculations affect simulated mold filling results significantly. Furthermore, simulated results of mold filling showed that porosities around the rib region of the tire-mold casting were probably caused by free surface turbulence and gas entrapment during mold filling. Simulated results also showed that changing the angle of ingate with runner may decrease porosity defects.
