| 摘要 |
PURPOSE:To suppress the temp. rise of a silicone rubber mold for casting and to suppress the deterioration of the casting mold by coating a heat resistant mold coating material on the surface of the casting mold. CONSTITUTION:A pattern OA of an impeller is fixed to the center of a master mold constituted of casting molds 1A, 2A and 3A and liquid silicone rubber 4A is poured into the spacing constituted of the master mold and the pattern OA. The pattern OA is pulled upward to form a cavity part 8A of a casting mold after a silicone rubber mold 7A is obtd. upon solidification of the silicone rubber. A heat resistant mold coating material 9A is then coated by spraying on the surface of the mold 7A. The mold 1A is removed and in turn , a reinforcing metallic mold 10A worked with a cooling water passing 11A on the surface is mounted to the lower part of the mold 7A. A casting mold 12A for a feeder head is mounted in place of the mold 3A. A molten metal 13A is poured into the mold while cooling water is passed in the cooling water passage 11A between the mold 7A and the mold 10A. The casting is removed from the mold upon solidification of the melt 15A of the poured Al alloy and is finished, by which the Al alloy impeller is obtd. |
