Golf club head and method of manufacturing the same

Abstract

A golf club head comprises a face portion formed by: forging a beta type titanium alloy while keeping the temperature of the alloy lower than the lower critical solution temperature of the alloy; and aging the forged alloy under the lower critical solution temperature Tc so as not to become a solution state. A method of manufacturing a golf club head comprises: preparing a billet of a beta type titanium alloy; forging the billet into the face member while keeping the temperature of the billet lower than the lower critical solution temperature Tc of the beta type titanium alloy; and aging the face member under the lower critical solution temperature Tc so as not to become a solution state.

1 . A golf club head comprising a face portion whose front face defines a club face for hitting a ball, wherein the face portion is formed by: 
 forging a beta type titanium alloy while keeping the temperature of the alloy lower than the lower critical solution temperature of the alloy; and    aging the forged alloy under the lower critical solution temperature Tc so as not to become a solution state.    
     
     
         2 . A method of manufacturing a golf club head, the golf club head comprising a face member comprising a face portion whose front face defines a club face for hitting a ball, and a main body to which the face member is attached, the method comprising: 
 preparing a billet of a beta type titanium alloy;    forging the billet into the face member while keeping the temperature of the billet lower than the lower critical solution temperature Tc of the beta type titanium alloy; and    aging the face member under the lower critical solution temperature Tc so as not to become a solution state.    
     
     
         3 . A golf club head according to  claim 1 , wherein 
 the temperature of the hot forging is not less than Tc-50 deg.C and not more than Tc-20 deg.C.    
     
     
         4 . A golf club head according to  claim 1  or  2 , wherein 
 the face portion is provided with a backward extension, the backward extension extending from an edge of the face portion and formed integrally with the face portion through said forging, and the backward extension is welded to a main body of the head which is formed by casting.  
 
     
     
         5 . A method according to  claim 2 , wherein 
 the temperature of the hot forging is not less than Tc-50 deg.C and not more than Tc-20 deg.C.    
     
     
         6 . A method according to  claim 2 , which further comprises 
 casting the main body.    
     
     
         7 . A method according to  claim 2 , wherein 
 the face member further comprises a backward extension extending from an edge of the face portion to be welded to the main body.    
     
     
         8 . A method according to  claim 2 ,  5 ,  6  or  7 , which further comprises 
 welding the face member to the main body before aging the face member.