Metal alloy and jewelry articles formed therefrom

Abstract

An article is formed of a metal alloy that includes the following constituents: (a) cobalt in an amount of between about 50.0% to about 51.0% by weight of the article; (b) tungsten in an amount of between about 21.0% to about 22.0% by weight of the article; (c) chromium in an amount of about 22.0% by weight of the article; (d) nickel in an amount of between about 2.5% to about 3.0% by weight; and (e) molybdenum in an amount of about 5.0% by weight. The article can be in the form of a jewelry article, such as a ring, a bracelet, a necklace, or an earring and can be formed by a shell casting process.

What is claimed is: 
     
         1 . An article formed of a metal alloy comprising:
 cobalt in an amount of between about 50.0% to about 51.0% by weight of the article;   tungsten in an amount of between about 21.0% to about 22.0% by weight of the article;   chromium in an amount of about 22.0% by weight of the article;   nickel in an amount of between about 2.5% to about 3.0% by weight; and   molybdenum in an amount of about 5.0% by weight.   
     
     
         2 . The article of  claim 1 , wherein the article comprises a jewelry article. 
     
     
         3 . The article of  claim 2 , wherein the jewelry article is selected from the group consisting of a ring, a bracelet, a necklace, a pendant, and an earring. 
     
     
         4 . The article of  claim 1 , wherein the article is formed by a shell casting process. 
     
     
         5 . The article of  claim 1 , wherein the metal alloy has a melting point of between about 1495° C. and about 1910° C. 
     
     
         6 . The article of  claim 1 , wherein the metal alloy has a hardness value on a Rockwell scale of between HRC40 and HRC42. 
     
     
         7 . The article of  claim 1 , wherein the metal alloy has a density of about 10.2 g/cm. 
     
     
         8 . The article of  claim 1 , wherein the metal alloy is shell castable and can be machined after being formed by a shell casting process. 
     
     
         9 . A method forming a scratch resistant, machinable article of jewelry comprising the steps of:
 preparing a metal alloy that comprises:
 cobalt in an amount of between about 50.0% to about 51.0% by weight of the article; 
 tungsten in an amount of between about 21.0% to about 22.0% by weight of the article; 
 chromium in an amount of about 22.0% by weight of the article; 
 nickel in an amount of between about 2.5% to about 3.0% by weight; and 
 molybdenum in an amount of about 5.0% by weight; 
   pouring the metal alloy in a melted state into a mold; and   forming the jewelry article by means of a shell casting process, wherein the formed jewelry article is at least substantially scratch resistant, yet flexible, and is machinable and of such hardness that a stone can be set directly into the jewelry article.   
     
     
         10 . A method forming a scratch resistant, machinable article of jewelry comprising the steps of:
 preparing a metal alloy that at least includes:
 cobalt in an amount of between about 50.0% to about 51.0% by weight of the article; and 
 tungsten in an amount of between about 21.0% to about 22.0% by weight of the article; 
   pouring the metal alloy in a melted state into a mold; and   forming the jewelry article by means of a shell casting process, wherein the formed jewelry article is at least substantially scratch resistant, yet flexible, and is machinable and of such hardness that a stone can be set directly into the jewelry article.   
     
     
         11 . The method of  claim 10 , wherein the metal alloy includes carbon in an amount up to about 2% by weight of the article. 
     
     
         12 . The method of  claim 10 , wherein the metal alloy further includes chromium, nickel and molybdenum. 
     
     
         13 . A jewelry article formed of a metal alloy that undergoes a shell casting process to form a blank that is then processed to form the jewelry article, wherein the metal alloy includes cobalt present in an amount between 20.0% to about 60.0% by weight of the article and tungsten present in an amount between 20.0% to about 60.0% by weight of the article. 
     
     
         14 . The jewelry article of  claim 13 , wherein the blank is processed by a machining process. 
     
     
         15 . The jewelry article of  claim 13 , wherein the cobalt is present in an amount of between about 50.0% to about 51.0% by weight of the article; and the tungsten is present in an amount of between about 21.0% to about 22.0% by weight of the article. 
     
     
         16 . A jewelry article formed of a metal alloy comprising:
 cobalt in an amount of between about 20.0% to about 60.0% by weight of the article; and   tungsten in an amount of between about 20.0% to about 60.0% by weight of the article;   wherein the jewelry article is formed of a blank that is formed of the metal alloy by a shell casting process;   wherein the blank is machinable.