Multi-stage forging process

Abstract

A method of manufacturing a forged iron type golf club head with a cavity. The method of manufacturing comprises forming a billet into an intermediate club head body with a strike face comprising an upper region and a lower region; hot pressing a cavity into the rear portion of the intermediate body; and bending the strike face of the intermediate club head body to form a golf club head with a cavity and a planar strike face. Other embodiments are disclosed.

What is claimed is: 
     
         1 . A forged golf club head comprising:
 a club head body comprising a sole, a top rail, a strike face, a back wall of the strike face, and a rear portion;
 wherein the strike face comprises a heel end, a toe end, an upper region, and a lower region; 
 wherein the rear portion of the body has an upper edge and a nonlinear outer periphery; 
   a cavity formed between the rear portion and the back wall of the strike face;
 wherein the cavity comprises a volume between 3.5 cc and 6.5 cc; 
 wherein the club head body is forged from a single solid billet; and 
   wherein the club head body comprises a tighter grain structure than a similar cast club head body.   
     
     
         2 . The forged golf club head of  claim 1 , wherein the single solid billet comprises at least two metals. 
     
     
         3 . The forged golf club head of  claim 1 , wherein the single solid billet comprises one or more of the following metals: 8620 alloy steel, S25C steel, carbon steel, maraging steel, stainless steel, stainless steel alloy, tungsten, aluminum, aluminum alloy, or any metal suitable for forging. 
     
     
         4 . The forged golf club head of  claim 1 , wherein the single solid billet comprises two or more of the following metals: 8620 alloy steel, S25C steel, carbon steel, maraging steel, stainless steel, stainless steel alloy, tungsten, aluminum, aluminum alloy, or any metal suitable for forging. 
     
     
         5 . The forged golf club head of  claim 1 , wherein the single solid billet comprises two or more metals, wherein at least one of the metals is 8620 alloy steel and at least one of the metals is tungsten. 
     
     
         6 . The forged golf club head of  claim 1 , wherein the single solid billet does not monolithically encase any other material. 
     
     
         7 . The forged golf club head of  claim 1 , further comprising an insert fixed within the cavity. 
     
     
         8 . The forged golf club head of  claim 7 , wherein the insert occupies between 95% and 100% of the volume of the cavity. 
     
     
         9 . The forged golf club head of  claim 1 , wherein the cavity of the golf club head extends in a direction from the heel end to the toe end. 
     
     
         10 . The forged golf club head of  claim 1 , wherein the cavity comprises a substantially triangular, rectangular, square, semi-circular, parabolic, or trapezoidal cross section. 
     
     
         11 . The forged golf club head of  claim 7 , wherein the insert that is fixed within the cavity comprises a mass ranging between 1.0 g and approximately 30.0 g. 
     
     
         12 . The forged golf club head of  claim 7 , wherein the insert that is fixed within the cavity comprises a density ranging between 1.0 g/cc and approximately 20.0 g/cc. 
     
     
         13 . The forged golf club head of  claim 7 , wherein the insert can be fixed within the cavity via adhesion, press-fitting, mechanical fastening, or any other suitable method of securing the insert. 
     
     
         14 . The forged golf club head of  claim 13 , wherein the insert is affixed to an interior surface wall of the cavity. 
     
     
         15 . The forged golf club head of  claim 1 , wherein the cavity extends in a direction from the heel end to the toe end. 
     
     
         16 . The forged golf club head of  claim 1 , wherein the club head body comprises a loft angle between 19° and 60°. 
     
     
         17 . The forged golf club head of  claim 1 , wherein the cavity is formed through one or more processes selected from the group consisting of hot pressing, machining, milling, drilling, and machine punching. 
     
     
         18 . The forged golf club head of  claim 1 , wherein the cavity comprises a depth between 0.25 inches and 1.0 inch. 
     
     
         19 . The forged golf club head of  claim 7 , wherein the insert is formed of one or more materials selected from the group consisting of a thermoplastic urethane, a thermoplastic elastomeric polymer, a hybrid plastic, an elastomeric polymer, aluminum, steel, and tungsten. 
     
     
         20 . The forged golf club head of  claim 1 , further comprising:
 a ground plane tangential and parallel to the sole;   an intersection plane parallel to the ground plane and perpendicular to the lower region of the strike face;   a cavity axis passing through a nadir of the cavity;   a press angle measured between the cavity axis and the intersection plane;   
       wherein the cavity axis exactly bisects the cavity and is equidistant from interior surface walls of the cavity; and 
       wherein the press angle is between 60° and 90°.