Patent ID: 6662852
Filing Date: 2003-12-16
Classification: B22D,C22C

Abstract:
A method of forming porosity-free, near net shape articles containing elevated melting temperature alloys, comprising:providing a liquid metal impermeable ceramic mold having a wall thickness defined by internal and external surfaces spaced from each other by a distance of from about 2 mm to about 6 mm and an opening disposed in an upper portion adapted to tightly receive a punch member therethrough; heating said ceramic mold; providing an alloy steel die having an internal cavity adapted to receive said ceramic mold therein; heating the alloy steel die; inserting the heated ceramic mold into the internal cavity of the alloy steel die; pouring a molten elevated melting temperature metal into the ceramic mold; lowering the punch member through the opening in the upper portion of the ceramic mold, bringing said punch member into intimate contact with the molten metal poured into the ceramic mold; continue lowering the punch member to create pressure on said molten metal sufficient to form an essentially porosity-free article having a net shape defined by the internal surface of the ceramic mold; cooling the alloy steel die, the ceramic mold, and the metal cast in the mold, thereby forming a solidified cast article in the mold; and, removing the solidified cast article from the mold.