Low Silver, Low Nickel Brazing Material

Abstract

A homogenous brazing material essentially consisting of relatively low amounts of silver and nickel together with copper, zinc, and other constituents is provided. The brazing material has a working temperature exceeding 630° F. and is preferably between about 1250° F. and 1500° F. The brazing material preferably has about 30 percent by weight of silver, about 36 percent by weight of copper, about 32 percent by weight of zinc, and about 2 percent by weight of nickel. The addition of nickel in the above-specified amount improves resistance against interface corrosion in aqueous solutions, aids in the strength of the alloy, and provides improved wettability on ferrous and non-ferrous substrates. The brazing material may also include a flux, such as a core or a coating.

We claim: 
     
         1 . A brazing material consisting essentially of
 less than approximately 35 percent by weight of silver;   less than approximately 40 percent by weight of copper;   more than 18 percent by weight of zinc; and   from approximately 1.75 percent by weight to approximately 2.25 percent by weight of nickel.   
     
     
         2 . The material of  claim 1  having silver in an amount less than 32 percent by weight of silver. 
     
     
         3 . The material of  claim 2  having silver in an amount less than 31 percent by weight of silver. 
     
     
         4 . The material of  claim 3  having from approximately 29 percent by weight to approximately 31 percent by weight of silver. 
     
     
         5 . The material of  claim 1  having from approximately 31 percent by weight to approximately 40 percent by weight of zinc. 
     
     
         6 . The material of  claim 1  having copper in an amount less than 38 percent by weight. 
     
     
         7 . The material of  claim 6  having copper in an amount less than approximately 37 percent by weight. 
     
     
         8 . The material of  claim 7  having from approximately 35 percent by W eight to approximately 37 percent by weight of copper. 
     
     
         9 . The material of  claim 1  having a working temperature greater than approximately 630° F. 
     
     
         10 . The material of  claim 9  having a working temperature of between 1250° F. and 1450° F. 
     
     
         11 . The material of  claim 1  in the form of at least one of a strip, a wire, a ring, a washer, a powder, and a paste. 
     
     
         12 . The material of  claim 1  configured for at least one of:
 use with torch, induction, furnace or other heating methods that are performed in open air and require the use of a flux; and 
 controlled atmosphere heating without the use of a flux. 
 
     
     
         13 . The material of  claim 1  having less than 0.20 percent by weight of indium, gallium, tin, aluminum, and titanium. 
     
     
         14 . A brazing material essentially consisting of:
 copper;   zinc;   nickel;   silver;   less than six percent by weight of cadmium;   trace constituents amounting to no more than 0.15 percent by weight of the total material composition; and   the brazing material having a working temperature exceeding 630° F.   
     
     
         15 . The material of  claim 14  having from approximately 29 percent by weight to approximately 31 percent by weight of silver. 
     
     
         16 . The material of  claim 14  having from approximately 1.75 percent by weight to approximately 225 percent by weight of nickel. 
     
     
         17 . The material of  claim 14  having from approximately 31 percent by weight to approximately 33 percent by weight of zinc. 
     
     
         18 . The material of  claim 14  having from approximately 35 percent by weight to approximately 37 percent by weight of copper. 
     
     
         19 . The material of  claim 14  having a working temperature between approximately 1250° F. to approximately 1450° F. 
     
     
         20 . A brazing material having a total composition consisting essentially of:
 from approximately 20 percent by weight to approximately 60 percent by weight of silver;   from approximately 20 percent by weight to approximately 60 percent by weight of copper:   from approximately 31 percent to approximately 40 percent by weigh of zinc;   from approximately 0.5 percent by weight to approximately 5.00 percent by weight of nickel; and   trace elements amounting to no more than approximately 0.15 percent by weight of the total composition.