Unit Cell Titanium Casting

Abstract

A system ( 5 ) and method ( 800 ) for unit cell casting of titanium or titanium-alloys is disclosed herein. The system ( 5 ) comprises an external chamber ( 45 ), a crucible ( 10 ) positioned within the external chamber ( 45 ), an induction coil ( 15 ) positioned around the crucible, an internal chamber ( 40 ) positioned within the external chamber ( 45 ), and a mold ( 30 ) positioned within the internal chamber ( 40 ). The external chamber ( 45 ) is evacuated and a pressurized gas is injected into the evacuated external chamber ( 45 ) to create a pressurized external chamber ( 45 ). An ingot ( 20 ) is melted within the crucible utilizing induction heating generated by the induction coil ( 15 ). The internal chamber ( 40 ) is evacuated to create an evacuated internal chamber ( 40 ). The titanium alloy material of the ingot ( 20 ) is completely transferred into the mold ( 30 ) from the crucible ( 10 ) using a pressure differential created between the external chamber ( 45 ) and the internal chamber ( 40 ).

We claim as our invention the following: 
     
         1 . A method for unit cell casting of titanium or titanium-alloys, the method comprising:
 evacuating an external chamber to create an evacuated external chamber wherein a crucible containing a titanium alloy ingot is positioned therein;   injecting a pressurized gas into the evacuated external chamber to create a pressurized external chamber;   melting the titanium alloy ingot within the crucible utilizing induction heating generated by an induction coil positioned around the crucible;   evacuating the internal chamber to create an evacuated internal chamber, wherein a mold is positioned within the internal chamber; and   transferring the completely melted titanium alloy material into the mold from the crucible using a pressure differential created between the external chamber and the internal chamber;   wherein a frequency generated in the induction coil ranges from 1 kilo-Hertz to 50 kilo-Hertz, and a power ranges from 15 kilo-Watts to 50 kilo-Watts;   wherein an atmospheric pressure of the evacuated internal chamber ranges from 3×10 −2  atmosphere to 9.87×10 −7  atmosphere;   wherein an atmospheric pressure of the evacuated internal chamber ranges from 9.87×10 −7  atmosphere to 9.87×10 −13  atmosphere.   
     
     
         2 . The method according to  claim 1  wherein the pressurized gas is argon. 
     
     
         3 . The method according to  claim 1  wherein the mold is covered in a kaolin wool insulating material. 
     
     
         4 . The method according to  claim 1  further comprising heating the mold using an infrared heating unit positioned within the internal chamber to create a heated mold. 
     
     
         5 . The method according to  claim 1  wherein the mold is for a thin-walled golf club head. 
     
     
         6 . The method according to  claim 1  wherein the mold is for an article having a wall thickness less than 0.250 inch. 
     
     
         7 . The method according to  claim 1  wherein the induction melting time ranges from 30 seconds to 90 seconds. 
     
     
         8 . The method according to  claim 1  wherein the crucible is composed of two yttria-based primary crucible layers, wherein a first primary crucible layer has a thickness ranging from 0.010 inch to 0.060 inch, and a second primary crucible layer has a thickness ranging from 0.001 inch to 0.020 inch. 
     
     
         9 . The method according to  claim 7  further comprising a silica based backup layer. 
     
     
         10 . The method according to  claim 1  further comprising cooling the titanium alloy within the mold. 
     
     
         11 . The method according to  claim 1  wherein the induction coil is positioned around a bottom section of the crucible. 
     
     
         12 . The method according to  claim 1  wherein the induction coil is positioned around an upper section of the crucible. 
     
     
         13 . A system for unit cell casting of titanium or titanium-alloys, the method comprising:
 an external chamber;   a ceramic crucible positioned within the external chamber;   an induction coil positioned around the ceramic crucible;   an internal chamber positioned within the external chamber;   a pattern mold cradle within the internal chamber; and   a mold positioned within the pattern mold cradle within the internal chamber;   wherein the external chamber is evacuated to create an evacuated external chamber wherein the ceramic crucible contains a titanium alloy ingot positioned therein;   wherein a pressurized gas is injected into the evacuated external chamber to create a pressurized external chamber;   wherein the titanium alloy ingot is melted within the ceramic crucible utilizing induction heating generated by the induction coil positioned around the ceramic crucible;   wherein the internal chamber is evacuated to create an evacuated internal chamber;   wherein the titanium alloy material is completely transferred into the mold from the crucible using a pressure differential created between the external chamber and the internal chamber.   
     
     
         14 . The system according to  claim 13  further comprising an infrared heating unit within the internal chamber, wherein the mold is heated using an infrared heating unit positioned within the internal chamber to create a heated mold. 
     
     
         15 . The system according to  claim 13  wherein the mold is for a thin-walled golf club head. 
     
     
         16 . The system according to  claim 13  wherein the mold is for an article having a wall thickness less than 0.250 inch. 
     
     
         17 . The system according to  claim 13  wherein the ceramic crucible is composed of two yttria-based primary crucible layers, wherein a first primary crucible layer has a thickness ranging from 0.010 inch to 0.060 inch, and a second primary crucible layer has a thickness ranging from 0.001 inch to 0.020 inch. 
     
     
         18 . The system according to  claim 13  wherein the induction coil is positioned around a bottom section of the ceramic crucible. 
     
     
         19 . The system according to  claim 13  wherein the induction coil is positioned around an upper section of the ceramic crucible. 
     
     
         20 . The system according to  claim 13  wherein the mold is covered in a kaolin wool insulating material.