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:
 positioning a mold within an internal chamber, wherein a pressure differential between the internal chamber and an external chamber is at a minimum;   evacuating an external chamber to create an evacuated external chamber wherein a ceramic crucible containing a titanium alloy ingot is positioned therein;   evacuating the internal chamber to create an evacuated internal chamber having a pressure no greater than 3×10 −2  atmosphere, wherein a pressure differential between the external chamber and the internal chamber is at minimum;   injecting a pressurized gas into the evacuated external chamber to create a pressurized external chamber with a pressure in excess of 1 atm, wherein the pressure differential between the external chamber and the internal chamber is maximized;   melting the titanium alloy ingot within the ceramic crucible utilizing induction heating generated by an induction coil positioned around the ceramic crucible;   generating an electromagnetic field during the melting step, the electromagnetic field holding the molten titanium within the ceramic crucible;   ceasing the electromagnetic field;   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 high pressure differential in maintained between the external chamber and the internal chamber during the transfer of the melted titanium alloy material;   wherein the PLC controls the generation of the electromagnetic field to correspond to the complete melting of the titanium alloy ingot in the ceramic crucible;   wherein the pressure of the internal chamber and the pressure of the external chamber are monitored and communicated to the PLC during the casting process, and wherein the PLC controls the casting process based on the pressure of the internal chamber and the pressure of the external chamber.   
     
     
         2 . The method according to  claim 1  wherein the pressurized gas is argon. 
     
     
         3 . The method according to  claim 1  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. 
     
     
         4 . The method according to  claim 1  wherein an atmospheric pressure of the evacuated internal chamber ranges from 3×10 −2  atmosphere to 9.87×10 −7  atmosphere. 
     
     
         5 . The method according to  claim 1  wherein a copper coil positioned around the opening of the ceramic crucible is used to generate the electromagnetic field. 
     
     
         6 . The method according to  claim 1  wherein ceasing the electromagnetic field allows for a seal at the opening of the ceramic crucible to melt allowing for the transfer of the molten material from the ceramic crucible into the mold. 
     
     
         7 . The method according to  claim 1  wherein the PLC determines when to melt the titanium alloy based on the pressures of the internal chamber and the external chamber. 
     
     
         8 . The method according to  claim 7  wherein the PLC determines when to change the pressure of internal chamber and the external chamber. 
     
     
         9 . The method according to  claim 1  wherein an atmospheric pressure of the evacuated internal chamber ranges from 9.87×10 −7  atmosphere to 9.87×10 −13  atmosphere 
     
     
         10 . A system method for unit cell casting of titanium or titanium-alloys, the system comprising:
 an external chamber;   a ceramic crucible positioned within the external chamber;   an electromagnetic field generator centered about an opening of the ceramic crucible;   an induction coil positioned around a bottom section of the ceramic crucible;   an internal chamber positioned within the external chamber; and   a mold positioned within the internal chamber;   a first vacuum gauge positioned within the internal chamber;   a second vacuum gauge positioned within the external chamber;   a PLC in communication with the first vacuum gauge, the second vacuum gauge, and the induction coil;   wherein a minimal pressure differential in maintained between the external chamber and the internal chamber prior to the melting of the titanium alloy ingot;   wherein the pressure of the internal chamber and the pressure of the external chamber are monitored and communicated to the PLC during the casting process, and wherein the PLC controls the casting process based on the pressure of the internal chamber and the pressure of the external 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 PLC controls the generating of the electromagnetic field to correspond to the complete melting of the titanium alloy ingot in the ceramic crucible;   wherein the titanium alloy material is completely transferred into the mold from the crucible using a maximum pressure differential created between the external chamber and the internal chamber.   
     
     
         11 . 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 ceramic crucible containing a titanium alloy ingot is positioned therein;   evacuating the internal chamber to create an evacuated internal chamber having a pressure no greater than 3×10 −2  atmosphere;   melting the titanium alloy ingot within the ceramic crucible utilizing induction heating generated by an induction coil positioned around the ceramic crucible, wherein the external chamber and the internal chamber are at an equal pressurization;   injecting a pressurized gas into the evacuated external chamber to create a pressurized external chamber with a pressure in excess of 1 atmosphere, wherein the pressure differential is at a maximum;   generating an electromagnetic field during the melting step, the electromagnetic field holding the molten titanium within the ceramic crucible;   ceasing the electromagnetic field; and   utilizing a high pressure differential between the external chamber and the internal chamber to flow the completely melted titanium alloy material into the mold from the crucible.   
     
     
         12 . The method according to  claim 11  wherein the pressurized gas is argon. 
     
     
         13 . The method according to  claim 11  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. 
     
     
         14 . The method according to  claim 11  wherein an atmospheric pressure of the evacuated internal chamber ranges from 3×10 −2  atmosphere to 9.87×10 −7  atmosphere. 
     
     
         15 . The method according to  claim 11  wherein the mold is for a thin-walled golf club head. 
     
     
         16 . The method according to  claim 11  wherein the internal chamber is preheated at a temperature ranging from 1150° C. to 1250° C. 
     
     
         17 . The method according to  claim 11  wherein a PLC determines when to melt the titanium alloy based on the pressures of the internal chamber and the external chamber. 
     
     
         18 . The method according to  claim 11  wherein the PLC determines when to change the pressure of internal chamber and the external chamber. 
     
     
         19 . The method according to  claim 11  wherein an atmospheric pressure of the evacuated internal chamber ranges from 9.87×10 −7  atmosphere to 9.87×10 −13  atmosphere