Golf club head with composite face

Abstract

A novel material comprising collections of prepreg plies and a variable thickness core material such as sheet molding compound or metal, methods of forming said material, and golf clubs comprising said material are disclosed herein. Golf club heads having faces made of multiple materials, including a composite layer at least partially sandwiched between two metal layers, are also disclosed herein.

We claim: 
     
         1 . A method comprising:
 providing a golf club head comprising a face and a recess in the face;   providing a sheet molding compound;   providing a face cap;   molding the sheet molding compound into the recess such that a shallow recess is disposed in an exterior surface of the sheet molding compound; and   disposing the face cap within the shallow recess to form a smooth striking surface.   
     
     
         2 . The method of  claim 1 , further comprising the step of permanently affixing the face cap within the shallow recess with an adhesive. 
     
     
         3 . The method of  claim 1 , further comprising the step of polishing the striking surface. 
     
     
         4 . The method of  claim 1 , further comprising the step of coating the striking surface with a protective material. 
     
     
         5 . The method of  claim 1 , further comprising the step of forming grooves in the face cap. 
     
     
         6 . The method of  claim 5 , wherein the step of forming grooves in the face cap is performed before the step of disposing the face cap within the shallow recess to form a smooth striking surface. 
     
     
         7 . The method of  claim 1 , further comprising the step of forming through-holes in the face cap, and wherein the sheet molding compound is visible through the through-holes. 
     
     
         8 . The method of  claim 1 , wherein the face cap has a variable thickness. 
     
     
         9 . The method of  claim 1 , wherein the sheet molding compound has a variable thickness. 
     
     
         10 . A method comprising:
 providing a golf club head comprising a face and a recess in the face;   providing first and second pluralities of prepreg plies;   providing a sheet molding compound;   providing a face cap;   combining the sheet molding compound with the first and second pluralities of prepreg plies to form a combination material;   molding the combination material into the recess such that a shallow recess is disposed in an exterior surface of the sheet molding compound; and   disposing the face cap within the shallow recess to form a smooth striking surface,   wherein the combination material satisfies at least one equation selected from the group consisting of   
       
         
           
             
               
                 
                   Dxx 
                   Dyy 
                 
                 > 
                 
                   C 
                    
                   
                       
                   
                    
                   and 
                    
                   
                       
                   
                    
                   
                     Dyy 
                     Dxx 
                   
                 
                 > 
                 C 
               
               , 
             
           
         
         wherein D is the bending stiffness of the combination material, and 
         wherein C is at least 1 and is no more than 1.5. 
       
     
     
         11 . The method of  claim 10 , further comprising the step of permanently affixing the face cap within the shallow recess with an adhesive. 
     
     
         12 . The method of  claim 10 , further comprising the step of polishing the striking surface. 
     
     
         13 . The method of  claim 10 , further comprising the step of coating the striking surface with a protective material. 
     
     
         14 . The method of  claim 10 , further comprising the step of forming grooves in the face cap. 
     
     
         15 . The method of  claim 14 , wherein the step of forming grooves in the face cap is performed before the step of disposing the face cap within the shallow recess to form a smooth striking surface. 
     
     
         16 . The method of  claim 10 , further comprising the step of forming through-holes in the face cap, and wherein the combination material is visible through the through-holes. 
     
     
         17 . The method of  claim 10 , wherein the face cap has a variable thickness. 
     
     
         18 . The method of  claim 10 , wherein the sheet molding compound has a variable thickness.