On the defects of low-pressure die castings

Pistons were made by low-pressure die casting process. Aluminium alloys used for this process were JIS AC8A, AC8B and AC3A. The main defects occurred were gate solidification, misrun, internal defect, surface defect, and various kinds of shrinkage cavity, etc. The causes of defects were investigated except for the gate solidification and misrun. The result was that these defects were closely relevant to the die mold temperature and pouring speed.