Golf club head

Abstract

An iron-type golf club head has a face having a face surface of a flat surface, and a hosel which is continuous with the face on its heel side. A shaft insertion hole is disposed in the hosel. A protrusion protruding rearward in the vicinity of the center in a toe-heel direction is disposed. A material of the golf club head is pure iron having a high purity of at least 99.995%, for instance, a purity within a range of 99.995 to 99.9999%. The golf club head is subjected to carburizing so that carbon diffuses to a range of about 0.2 to 0.5 mm from the surface.

1 . A golf club head comprising: 
 a face made of a iron material which is carburized,    wherein the iron material is pure iron.    
   
   
       2 . The golf club head according to  claim 1 , 
 wherein purity of the pure iron is at least 99.8%.    
   
   
       3 . The golf club head according to  claim 1 , 
 wherein the golf club head is an iron-type golf club head.    
   
   
       4 . The golf club head according to  claim 2 , 
 wherein the golf club head is an iron-type golf club head.    
   
   
       5 . The golf club head according to  claim 3 , 
 wherein the iron-type golf club head has a loft angle of 25° or more.    
   
   
       6 . The golf club head according to  claim 4 , 
 wherein the iron-type golf club head has a loft angle of 25° or more.    
   
   
       7 . The golf club head according to  claim 3 , 
 wherein a thickness of the face in a vicinity of a center of gravity of the face falls within a range of 3.5 to 15 mm.    
   
   
       8 . The golf club head according to  claim 5 , 
 wherein a thickness of the face in a vicinity of a center of gravity of the face falls within a range of 3.5 to 15 mm.    
   
   
       9 . The golf club head according to  claim 7 , 
 wherein the face is of smaller thickness on a toe side and on a heel side than in the vicinity of the center of gravity of the face.    
   
   
       10 . The golf club head according to  claim 8 , 
 wherein the face is of smaller thickness on a toe side and on a heel side than in the vicinity of the center of gravity of the face.    
   
   
       11 . The golf club head according to  claim 1 , 
 wherein hardness of a surface of the face falls within a range of HV 180 to 900.