Golf club head having a nanocrystalline titanium alloy

Abstract

Embodiments of a golf club head and methods to manufacture such a golf club head are generally described herein. The golf club head generally includes at least one ball-striking face, which comprises a titanium alloy that is associated with an average grain size measuring no more than about 1 micron (μm) in the longest dimension. The golf club head is associated with a coefficient of restitution of about 0.847 or more when a ball impacts the ball-striking face.

What is claimed is: 
     
         1 . A golf club head comprising:
 at least one ball-striking face, wherein the ball-striking face comprises a titanium alloy that is associated with an average grain size measuring no more than about 1 micron (μm) in the longest dimension, wherein the titanium alloy comprises, by weight, about 5.50% to about 6.75% aluminum, about 3.5% to about 4.5% vanadium, and the balance titanium and incidental elements and impurities.   
     
     
         2 . The golf club head of  claim 1 , wherein the titanium alloy is associated with a yield strength of about 860 Megapascal (MPa) to about 1100 MPa. 
     
     
         3 . The golf club head of  claim 1 , wherein the titanium alloy is associated with a yield strength of about 1050 Megapascal (MPa) to about 1100 MPa. 
     
     
         4 . The golf club head of  claim 1 , wherein the golf club head is associated with a coefficient of restitution of about 0.847 or more when a ball impacts the ball-striking face. 
     
     
         5 . The golf club head of  claim 1 , wherein the golf club head is associated with a coefficient of restitution of about 0.840 or more when a ball impacts the ball-striking face at an incident ball speed of about 180 kilometers (km) per hour to about 200 km per hour. 
     
     
         6 . A golf club comprising:
 a shaft; and   a golf club head having a ball-striking face made of a titanium alloy, wherein the titanium alloy is associated with an average grain size measuring less than 1 μm in the longest dimension, wherein, the titanium alloy comprises by weight at least 5.5% aluminum, at least 1.8% tin, and the balance titanium and incidental elements and impurities.   
     
     
         7 . The golf club of  claim 6 , wherein the titanium alloy further comprises, by weight, at least 3.6% zirconium. 
     
     
         8 . The golf club of  claim 6 , wherein the titanium alloy further comprises, by weight, at least 1.8% molybdenum. 
     
     
         9 . The golf club of  claim 6 , wherein the titanium alloy further comprises, by weight, at least 3.6% zirconium and at least 1.8% molybdenum. 
     
     
         10 . The golf club of  claim 6 , wherein the golf club head is associated with a coefficient of restitution of about 0.847 or more when a ball impacts the ball-striking face. 
     
     
         11 . The golf club of  claim 6 , wherein the golf club head is associated with a coefficient of restitution of about 0.840 or more when a ball impacts the ball-striking face at an incident ball speed of about 180 kilometers (km) per hour to about 200 km per hour. 
     
     
         12 . The golf club of  claim 11 , wherein the titanium alloy is associated with a yield strength of about 860 Megapascal (MPa) to about 1100 MPa. 
     
     
         13 . A golf club comprising:
 a shaft; and   a golf club head having a ball-striking face made of a titanium alloy, wherein the titanium alloy is associated with an average grain size measuring less than 1 μm in the longest dimension, the golf club head being associated with a coefficient of restitution of about 0.847 or more when a ball impacts the ball-striking face.   
     
     
         14 . The golf club of  claim 13 , wherein the titanium alloy is associated with a yield strength of about 860 Megapascal (MPa) to about 1100 MPa. 
     
     
         15 . The golf club of  claim 14 , wherein the titanium alloy comprises, by weight, about 5.50% to about 6.75% aluminum, about 3.5% to about 4.5% vanadium, and the balance titanium and incidental elements and impurities. 
     
     
         16 . The golf club of  claim 14 , wherein the titanium alloy comprises, by weight, no at least 6% aluminum and at least 4% vanadium. 
     
     
         17 . The golf club of  claim 14  wherein, the titanium alloy comprises by weight at least 5.5% aluminum, at least 1.8% tin, and the balance titanium and incidental elements and impurities. 
     
     
         18 . The golf club of  claim 17 , wherein the titanium alloy further comprises, by weight, at least 3.6% zirconium. 
     
     
         19 . The golf club of  claim 17 , wherein the titanium alloy further comprises, by weight, at least 1.8% molybdenum. 
     
     
         20 . The golf club of  claim 17 , wherein the titanium alloy further comprises, by weight, at least 3.6% zirconium and at least 1.8% molybdenum.