Hot-chamber die casting systems and methods

Abstract

Hot-chamber die casting systems for casting aluminum, copper, titanium, and their alloys, as well as other high temperature and/or reactive metals. The hot-chamber die casting system comprises an injection system that includes a cylinder, a plunger reciprocable within the cylinder, and a gooseneck that defines a passage fluidically connected to a cylinder chamber within the cylinder, wherein surfaces of the cylinder, plunger, and gooseneck that contact a molten metal during injection casting are defined by a refractory material that does not react with the molten metal, or have been treated to reduce the rate of dissolution of their surface material into the molten metal during injection casting.

1 . A hot-chamber die casting system for injection casting a molten metal, the hot-chamber die casting system having an injection system that is at least partially immersed in a pool of the molten metal, the injection system comprising:
 a cylinder having a chamber therein;   a plunger reciprocable within the chamber of the cylinder; and   a gooseneck defining a passage fluidically connected to the chamber within the cylinder, the passage and the chamber defining a hot chamber of the hot-chamber die casting system;   wherein at least surfaces of the cylinder, plunger, and gooseneck that contact the molten metal during injection casting, or optionally the cylinder, plunger, and gooseneck in their entirety, are defined by one or more refractory metals or alloys thereof that do not react with the metal and/or exhibit dissolution rates with the molten metal that are less than the dissolution rates of ferrous alloys with the metal.   
     
     
         2 . The hot-chamber die casting system of  claim 1 , wherein each of the cylinder, plunger, and gooseneck consists of the one or more refractory metals or alloys thereof. 
     
     
         3 . The hot-chamber die casting system of  claim 1 , wherein each of the cylinder, plunger, and gooseneck comprises a bulk material and a shell material on the bulk material that defines the surfaces thereof that contact the molten metal during injection casting. 
     
     
         4 . The hot-chamber die casting system of  claim 3 , wherein the shell material is a coating applied to surfaces of the bulk material. 
     
     
         5 . The hot-chamber die casting system of  claim 3 , wherein the shell material is produced to have a cavity therein that is filled by injecting a liquid volume of the bulk material therein. 
     
     
         6 . A method of using the hot-chamber die casting system of  claim 1 , the method comprising:
 at last partially immersing the injection system in a pool of the molten metal; and   actuating the plunger to force a molten volume of the molten metal through the passage of the gooseneck and into a die mold cavity.   
     
     
         7 . The method of  claim 6 , wherein the molten metal is aluminum, copper, titanium, or an aluminum alloy, copper alloy, or titanium alloy. 
     
     
         8 . A casting formed by the method of  claim 6 . 
     
     
         9 . A hot-chamber die casting system for injection casting a molten metal, the hot-chamber die casting system having an injection system that is at least partially immersed in a pool of the molten metal, the injection system comprising:
 a cylinder having a chamber therein;   a plunger reciprocable within the chamber of the cylinder; and   a gooseneck defining a passage fluidically connected to the chamber within the cylinder, the passage and the chamber defining a hot chamber of the hot-chamber die casting system;   wherein each of the cylinder, plunger, and gooseneck comprises a bulk metallic material, and each of the cylinder, plunger, and gooseneck comprises refractory ceramic surfaces that contact the molten metal during injection casting and do not react with the molten metal.   
     
     
         10 . The hot-chamber die casting system of  claim 9 , wherein each of the cylinder, plunger and gooseneck comprises a shell material on the bulk metallic material thereof that defines the refractory ceramic surfaces thereof that contact the molten metal during injection casting, wherein the shell material comprises the refractory ceramic material. 
     
     
         11 . The hot-chamber die casting system of  claim 10 , wherein the shell material is a coating applied to surfaces of the bulk metallic material. 
     
     
         12 . The hot-chamber die casting system of  claim 10 , wherein the shell material is produced to have a cavity therein that is filled by injecting a liquid volume of the bulk metallic material therein. 
     
     
         13 . A method of using the hot-chamber die casting system of  claim 9 , the method comprising:
 at last partially immersing the injection system in a pool of the molten metal; and   actuating the plunger to force a molten volume of the molten metal through the passage of the gooseneck and into a die mold cavity.   
     
     
         14 . The method of  claim 13 , wherein the molten metal is aluminum, copper, titanium, or an aluminum, copper or titanium alloy. 
     
     
         15 . A casting formed by the method of  claim 13 . 
     
     
         16 . A hot-chamber die casting system for injection casting a molten metal, the hot-chamber die casting system having an injection system that is at least partially immersed in a pool of the molten metal, the injection system comprising:
 a cylinder having a chamber therein;   a plunger reciprocable within the chamber of the cylinder; and   a gooseneck defining a passage fluidically connected to the chamber within the cylinder, the passage and the chamber defining a hot chamber of the hot-chamber die casting system;   wherein the cylinder, plunger, and gooseneck are each formed of a ferrous material and surfaces of the cylinder, plunger, and gooseneck that contact the molten metal during injection casting have surface treatments to reduce the rate of dissolution of the ferrous material into the molten metal during injection casting.   
     
     
         17 . The hot-chamber die casting system of  claim 16 , wherein the surface treatments are nitride or carbo-nitride surface treatments. 
     
     
         18 . A method of using the hot-chamber die casting system of  claim 16 , the method comprising:
 at last partially immersing the injection system in a pool of the molten metal; and   actuating the plunger to force a molten volume of the molten metal through the passage of the gooseneck and into a die mold cavity.   
     
     
         19 . The method of  claim 18 , wherein the molten metal is aluminum, copper, titanium, or an aluminum, copper, or titanium alloy. 
     
     
         20 . A casting formed by the method of  claim 18 .