PURPOSE: To obtain superplasticity necessary for superplastic forging by capturing the globules by atomization of a gas in a mold, cooling the same quickly to a preform of fine crystals, heating the preform to a specific temp. by induction heating and resistance heating and subjecting the same to hydrostatic pressurizing under isopropic pressure of a pressure medium.
CONSTITUTION: A melt 2 of a superalloy raw material in a melting furnace 1 is charged into a tundish 3 by tilting the furnace 1 and is dropped by each small amt. into a gas atomizing chamber 4. An inert gas is injected at high velocity into the chamber 4 through a nozzle 5 to cool the melt 2 quickly and to pulverize the same. The powder is captured in a capturing device 6. A preform 7 of the fine crystals obtained in such a way is subjected to induction heating or to induction heating after resistance heating whereby the preform is heated up to the recrystallization temp. of the melt 2W the temp. lower by 150°C than said temp. The preform is hydrostatically prssurized by the isotropic pressure of the pressure medium at said temps., whereby the preform is compacted.
TAKIGAWA HIROSHI
OGATA KAZUO
ISHII MASARU
Next Patent: PRODUCTION OF POROUS SINTERED BODY OF STAINLESS STEEL POWDER