Dies for die casting aluminum and other metals

Abstract

A mold for use in die casting aluminum parts is made from an underaged Ni—Be alloy containing about 1.0 to 2.0 wt. % Be.

We claim:  
     
         1 . A tool for contacting a molten metal at elevated temperature, wherein the tool is made from a Ni—Be alloy containing about 1.0 to less than 3.0 wt. % Be.  
     
     
         2 . The tool of  claim 1 , wherein the tool is a mold or mold insert.  
     
     
         3 . The tool of  claim 2 , wherein the Ni—Be alloy has a thermal conductivity of at least about 20 Btu/ft.hr.F.  
     
     
         4 . The tool of  claim 3 , wherein Ni—Be alloy is underaged.  
     
     
         5 . The tool of  claim 2 , wherein the Ni—Be alloy has a thermal conductivity of at least about 25 Btu/ft.hr.° F.  
     
     
         6 . The tool of  claim 5 , wherein the hardness of the Ni—Be alloy is 90% or less of its peak aged hardness.  
     
     
         7 . The tool of  claim 6 , wherein the hardness of the Ni—Be alloy is 75% or less of its peak aged hardness.  
     
     
         8 . The tool of  claim 5 , wherein the Ni—Be alloy contains at least one additive selected from the group consisting of Al, C, Co, Cr, Cu, Fe, Mg, Mo, Ti, Y and the Rare Earth Elements.  
     
     
         9 . The tool of  claim 5 , wherein the alloy contains about 1.0 to 2.0 wt. % Be.  
     
     
         10 . A tool for contacting a molten metal at elevated temperature, wherein the tool is made from an underaged Ni—Be alloy, the amount of Be in the Ni—Be alloy being sufficient Be so that a continuous coating of beryllium oxide forms on the surfaces of the tool but not so great that the alloy becomes brittle.  
     
     
         11 . A process for solidification of a molten metal selected from aluminum, aluminum alloy, magnesium, magnesium alloy, copper, copper alloy, zinc and zinc alloy comprising charging the molten metal into a die, the die optionally having a die insert, and allowing the molten metal to solidify therein, wherein the die or die insert or both are made from a Ni—Be alloy containing about 1.0 to less than 3.0 wt. % Be.  
     
     
         12 . The process of  claim 11 , wherein the Ni—Be alloy contains about 1.0 to 2.0 wt. % Be.  
     
     
         13 . A Ni—Be alloy for use in making molds for solidifying molten metals, the alloy containing about 1.0 to 3.0 wt. % Be, the alloy having been underaged so that the hardness of the alloy is less than 90% of the hardness of a peak aged alloy of the same composition, the alloy having a thermal conductivity of at least about 20 Btu/ft.hr.° F.  
     
     
         14 . The alloy of  claim 13 , wherein the alloy contains about 1.0 to 2.0 wt. % Be.