White Tungsten Carbide Jewelry Article

Abstract

An improved jewelry article with a brilliant, preferably white, coating securely bonded to a substrate. The coating comprises predominantly chromium and, where a white finish is desired, a platinum group metal, preferably platinum. The substrate comprises predominantly tungsten carbide and a substantial amount of metal, preferably nickel. The coating is applied to the substrate using vapor deposition, such as physical vapor deposition. The metal and especially nickel will facilitate adhesion between the chromium in the coating and the substrate. The vapor deposition will further provide for superior adhesion as compared to traditional plating techniques. The improved jewelry article will maintain the brilliant, preferably white, finish of the coating due to the hard scratch resistant predominantly chromium coating and the improved adhesion between the coating and substrate.

1 . A improved jewelry article comprising:
 a substrate having an exterior surface, said substrate comprising predominantly tungsten carbide by weight, said substrate further comprising metal, said metal comprising at least about twenty percent of said substrate by weight;   a coating secured to said substrate via vapor deposition; said coating comprising predominantly chromium.   
     
     
         2 . An improved jewelry article according to  claim 1  wherein said coating covers substantially all of said exterior surface of said substrate. 
     
     
         3 . An improved jewelry article according to  claim 2  wherein said metal comprises at least about twenty-seven percent of said substrate by weight. 
     
     
         4 . An improved jewelry article according to  claim 2  wherein said metal comprises nickel and alloys thereof. 
     
     
         5 . An improved jewelry article according to  claim 4  wherein said nickel is dispersed throughout said substrate. 
     
     
         6 . An improved jewelry article according to  claim 5  wherein said metal further comprises molybdenum. 
     
     
         7 . An improved jewelry article according to  claim 6  wherein said molybdenum is dispersed throughout said substrate. 
     
     
         8 . An improved jewelry article according to  claim 7  wherein said coating further comprises a metal selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, and platinum. 
     
     
         9 . An improved jewelry article according to  claim 5  wherein said coating further comprises a metal selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, and platinum. 
     
     
         10 . An improved jewelry article according to  claim 9  wherein said coating is white. 
     
     
         11 . An improved jewelry article according to  claim 1  wherein said substrate is selected from the group consisting of rings, earrings, necklaces, bracelets, and pendants. 
     
     
         12 . An improved jewelry article according to  claim 11  wherein said substrate is a ring. 
     
     
         13 . An improved jewelry article according to  claim 1  wherein said substrate is formed by sintering. 
     
     
         14 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article comprising:
 applying a coating to a substrate via vapor deposition, said coating comprising predominantly chromium;   said substrate having an exterior surface, said substrate further comprising predominantly tungsten carbide by weight, said substrate further comprising metal, said metal comprising at least about twenty percent of said substrate by weight.   
     
     
         15 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 14  wherein said coating is applied to substantially all of said exterior surface of said substrate. 
     
     
         16 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 15  wherein said metal comprises at least about twenty-seven percent of said substrate by weight. 
     
     
         17 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 15  wherein said metal comprises nickel. 
     
     
         18 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 17  wherein said nickel is dispersed throughout said substrate. 
     
     
         19 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 18  wherein said metal further comprises molybdenum. 
     
     
         20 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 19  wherein said molybdenum is dispersed throughout said substrate. 
     
     
         21 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 20  wherein said coating further comprises a metal selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, and platinum. 
     
     
         22 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 18  wherein said coating further comprises a metal selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, and platinum. 
     
     
         23 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 22  wherein said coating is white. 
     
     
         24 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 14  wherein said substrate is selected from the group consisting of rings, earrings, necklaces, bracelets, and pendants. 
     
     
         25 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 24  wherein said substrate is a ring. 
     
     
         26 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 15  wherein said vapor deposition comprises physical vapor deposition. 
     
     
         27 . A method of applying a scratch resistant coating with a high degree of adhesion to a jewelry article according to  claim 26  wherein said physical vapor deposition comprises sputtering. 
     
     
         28 . An improved jewelry article according to  claim 27  wherein said substrate is formed by sintering.