| 摘要 |
PROBLEM TO BE SOLVED: To provide a low pressure casting method and a low pressure casting device with a simple constitution which can surely achieve the directive solidification of a molten metal, and a casting free from defects can be efficiently molded. SOLUTION: The low pressure casting device includes: a holding furnace 1 holding a molten metal M; a mold 2 arranged at the upper part of the holding furnace 1; a stroke 3 provided at the mold 2 and whose lower tip is dipped into the molten metal M held to the holding furnace 1; and a molten metal pushing-up means 4 feeding a pressurized fluid into the holding furnace 1, pushing up the molten metal M via the stroke 3 and filling the molten metal M into the mold 2. At the initial stage of pouring, a low temperature molten metal MA is fed into the mold 2, and a high temperature molten metal MB is fed into the mold 2 from the middle of the pouring. The temperature of the low temperature molten metal MA is held to the one lower than that of the high temperature molten metal MB, and further, it is contacted with the cavity 22 of the mold 2 whose temperature is low, thus directive solidification that the solidification of the molten metal M successively progresses from the tip part within the cavity 22 toward a pouring opening 23 can be achieved. COPYRIGHT: (C)2009,JPO&INPIT
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