Process for Thermal Spray Coating of a Golf Club Head and Golf Club Head with Thermally Sprayed Coating

Abstract

The disclosure relates to a process for coating a club face or striking surface of a club head of a golf club and also relates to a golf club. A coating is applied to a metallic substrate of the club head on at least a portion of the club face or striking surface by means of a thermal spray coating process. According to the disclosure, the process comprises processing the portion of the club face or striking surface with a laser beam before and after the application of the coating in order to provide the surface of the uncoated substrate and the surface of the coating with a predefined surface roughness, such as one having a roughness depth Rz of 50 μm±10%.

What is claimed is: 
     
         1 . Process for coating a club face or striking surface of a club head of a golf club, wherein a coating is applied to a metallic substrate of the club head on at least a portion of the club face or striking surface by means of a thermal spray coating process comprising processing the portion of the club face or striking surface with a laser beam before and after the application of the coating in order to provide the surface of the uncoated substrate and the surface of the coating with a predefined surface roughness. 
     
     
         2 . Process according to  claim 1 , wherein the surface of the uncoated substrate and the surface of the coating are provided with a roughness depth Rz according to DIN EN ISO 4287:2010 of Rz=50 μm±10%. 
     
     
         3 . Process according to  claim 1 , wherein the surface of the uncoated substrate and the surface of the coating are provided with an arithmetic mean surface roughness Ra according to DIN EN ISO 4287:2010 of Ra from 12 to 20 μm. 
     
     
         4 . Process according to  claim 1 , wherein the laser beam is emitted from a laser source having a laser power of 150 to 200 Watt. 
     
     
         5 . Process according to  claim 4 , wherein the laser source is a diode laser or a fiber laser. 
     
     
         6 . Process according to  claim 1 , wherein the laser beam is moved along identical predetermined paths across the surface of the uncoated substrate and across the surface of the coating. 
     
     
         7 . Process according to  claim 6 , wherein the laser beam is moved in parallel horizontal lines across the surface of the uncoated substrate and across the surface of the coating. 
     
     
         8 . Process according to  claim 1 , wherein the thermal spray coating process is a flame spray coating process or a high-velocity flame spray coating process. 
     
     
         9 . Process according to  claim 1 , wherein the coating is applied to a thickness of 0.2 to 0.5 mm. 
     
     
         10 . Process according to  claim 1 , wherein the coating comprises a coating material that is selected from the group consisting of WC/Co/Ni, WC/Co/Cr, Cr3C2/Ni/Cr, Ni und Cr. 
     
     
         11 . Process according to  claim 1 , wherein the coating material is a particulate powder having a particle size of 45±10 μm. 
     
     
         12 . Golf club having a club head, the club head comprising a metallic substrate and a club face or striking surface, wherein the metallic substrate is provided with a thermally sprayed coating on at least a portion of the club face or striking surface and wherein the surface of the coating and the surface of the uncoated substrate beneath the coating have the same surface roughness. 
     
     
         13 . Golf club according to  claim 12 , wherein the surface of the coating and the surface of the uncoated substrate have a roughness depth Rz according to DIN EN ISO 4287:2010 of Rz=50 μm±10%. 
     
     
         14 . Golf club according to  claim 12 , wherein the surface of the coating and the surface of the uncoated substrate have an arithmetic mean surface roughness Ra according to DIN EN ISO 4287:2010 of Ra from 12 to 20 μm. 
     
     
         15 . Golf club according to  claim 12 , wherein the coating has a thickness of 0.2 to 0.5 mm or a thickness of 0.3 to 0.4 mm. 
     
     
         16 . Golf club according to  claim 12 , wherein the coating comprises a coating material that is selected from the group consisting of WC/Co/Ni, WC/Co/Cr, Cr3C2/Ni/Cr, Ni und Cr. 
     
     
         17 . Golf club according to  claim 12 , wherein the surface of the coating, the surface of the metallic substrate beneath the coating, or both the surface of the coating and the surface of the metallic substrate beneath the coating have a plurality of small parallel grooves with a depth of less than 100 μm. 
     
     
         18 . Golf club according to  claim 12 , wherein the surface of the coating, the surface of the metallic substrate beneath the coating, or both the surface of the coating and the surface of the metallic substrate beneath the coating have a plurality of small parallel grooves that extend horizontally across the club face or striking surface. 
     
     
         19 . Golf club according to  claim 12 , wherein the golf club is a wedge or an iron from a 1 iron to a 9 iron. 
     
     
         20 . Golf club according to  claim 19 , wherein the club face or striking surface has a number of parallel grooves and wherein the coating is provided on portions of the club face or striking surface wedge that are disposed between the grooves.