COUNTERGRAVITY CASTING METHOD AND APPARATUS

摘要

Countergravity casting of metals and metal alloys provides for melting of th e metallic material under subambient pressure, evacuation of a gas permeable o r impermeable mold (15) under subambient pressure, and controlled, rapid filli ng of the mold (15) while it is maintained under the subambient pressure by applying gas pressure locally on the molten metallic material in a sealed space defined by engagement of a mold base (13) and a melting vessel with a seal therebetween. The gas pressure applied locally in the sealed space establishes a differential pressure on the molten metallic material to force it upwardly through the fill tube (16) into the mold (15).