| 摘要 |
PURPOSE:To prevent the casting defect by making the temperature of molten metal to be poured to the lost foam pattern to the temperature higher by the specific temperature than the liquidus line of the casting material which compose the molten metal, and treating with deoxidizing so that the oxygen content in the casting is made under than the specific value. CONSTITUTION:The lost foam pattern 4 of the foamed resin which is disappeared with the heat of the molten metal is embedded in the casting sand 3, and the above lost foam pattern is poured with the molten metal. The temperature of the molten metal of the above pouring time is made to the temperature by 80-230 deg.C higher than the liquidus line of the casting material which compose the molten metal. At the same time, the above molten metal is treated with deoxidizing so that the oxygen content in the casting products is made under <=180ppm. Therefore, the reduction of fluidity is prevented, that is, the misrun is prevented, and the gas defect caused on the gas emitted out from the molten metal on the solidification process can be also prevented. |
