Master alloy production for glassy aluminum-based alloys

Abstract

Apparatus is provided for forming aluminum alloy ingots in a sealed chamber having a source of inert gas using a crucible positioned inside the chamber for melting aluminum alloy powder. The crucible has a solid top and a source of inert gas therein. An outlet in the crucible is positioned to draw molten alloy from the crucible at a point proximate the lowest point in the crucible. A tundish adapted to control the flow of molten alloy from the crucible on a path to at least one ingot mold out of the sealed chamber

1 . A method of forming aluminum alloy ingots, comprising the steps of:
 melting aluminum alloy feed stock in a crucible having an inert atmosphere;   drawing molten alloy from the crucible at a point below the inert atmosphere; and   maintaining an inert atmosphere during the flow of alloy from the crucible to a mold.   
     
     
         2 . The method of  claim 1 , wherein the outlet of the crucible means is proximate the bottom of the crucible. 
     
     
         3 . The method of  claim 1 , wherein the outlet of the crucible is positioned to flow alloy out of the lower side of the crucible. 
     
     
         4 . The method of  claim 1 , wherein the the molten alloy is transferred from the crucible to the mold is performed with a launder having a cylindrical or other cross section. 
     
     
         5 . The method of  claim 1 , wherein the inert gas is argon. 
     
     
         6 . The method of  claim 1 , wherein the alloy is a devitrified glass-forming aluminum alloys having a nanometer-sized grain structure and nanometer-sized intermetallic phase or phases. 
     
     
         7 . A method of forming aluminum alloy ingots, comprising the steps of:
 melting a quantity of aluminum alloy feed stock in a crucible, the crucible being positioned inside a chamber having an inert atmosphere at a pressure sufficient to drive out ambient atmosphere, the crucible melting the feed stock to a molten alloy;   removing molten alloy from the crucible through an outlet at a point proximate the lowest point of the crucible; and   controlling the flow of molten alloy from the crucible to at least one ingot mold while maintaining an inert atmosphere, the flow being controlled with a tundish; and   removing the at least one ingot mold from an inert atmosphere.   
     
     
         8 . The method of  claim 7 , wherein the outlet means on the crucible means is positioned to flow alloy out the bottom of the crucible. 
     
     
         9 . The method of  claim 7 , wherein the outlet means on the crucible means is positioned to flow alloy out of the lower side of the crucible. 
     
     
         10 . The method of  claim 7 , wherein the outlet includes a launder having a cylindrical or other cross section for transferring the molten alloy from the crucible to the tundish. 
     
     
         11 . The method of  claim 7 , wherein the inert gas is argon. 
     
     
         12 . The method of  claim 7 , which further includes the step of maintaining the dew point in the crucible between −35° F. (−37.2° C.) and −110° F. (−78.9° C.) or lower. 
     
     
         13 . The method of  claim 7 , wherein the alloy is a devitrified glass-forming aluminum alloy having a nanometer-sized grain structure and nanometer-sized intermetallic phase or phases. 
     
     
         14 . An aluminum alloy formed by the method of  claim 13 .