To provide an investment casting method for metallic material in a mold and on the surface of a core, is improved and cast void is reduced.
Molten metallic material is cast into the mold which is made by providing a barrier for reducing the permeability of gas passed through a mold wall forming the mold surface being in contact with the molten metallic material at the most inner part side. The molten metallic material is cast into the mold in a furnace in a casting chamber with gravity at a first pressure having lower than the circumferential pressure. Thereafter, the higher gas pressure than primary pressure is supplied into the casting chamber so rapidly enough to reduce or eliminate the local void existing in the casting solidified in the mold.
KILINSKI BART M
BRINEGAR JOHN R
MURPHY BRAD J
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