| 摘要 |
PURPOSE:To obtain an as-cast product without any defect in thick part, by arranging a dummy member, which is made of the material having melting point lower than that of a raw material for casting, near the the thick part in a die and removing resolidified dummy member after executing die casting. CONSTITUTION:By pressurizing a plunger during operating a die casting apparatus 10, molten aluminum having high temp. is pressed in a cavity 26 through a plunger sleeve 38. The molten aluminum is brought into contact with inserts 48, 50 in the thick part forming bolt hole and filler hole in the cavity 26. The melting point of the inserts 48, 50 is low, because of zinc alloy, and as it resolidifies after all of the molten aluminum has solidified, the defects of shrinkage hole, etc., are concentrately developed at the positions, where the inserts 48, 50 are inserted. After the parts of the inserts 48, 50 solidifies, an ejecting device 28 is worked and the as-cast product is ejected to out of the die by ejecting pins 34, 36. The insert part is removed by cutting and the product without any defect in the bolt hole, etc., is obtd.
|
