Phosphorus-copper-antimony-tin brazing alloy

Abstract

A phosphorus-copper based brazing alloy comprising by weight: 6.0% to 7.0% phosphorus; about 2% to about 8% tin; about 2% antimony; and the balance copper. A process of using this alloy to produce a brazed joint with a raised shoulder and with little black oxide.

What is claimed:  
     
         1 . A phosphorus-copper based alloy comprising by weight: 
 a) 6.0% to 7.0% phosphorus;    b) about 2% to about 8% tin;    c) about 2% antimony; and    d) the balance copper    wherein the alloy produces a brazed joint with a substantial shoulder and without substantial black oxide.    
     
     
         2 . The phosphorus-copper based alloy of  claim 1 , wherein the percentage of phosphorus is 6.75%.  
     
     
         3 . The phosphorus-copper based alloy of  claim 1 , wherein the percentage of phosphorus is 6.7% and the percentage of tin is 6%.  
     
     
         4 . The phosphorus-copper based alloy of  claim 1 , wherein the solidus temperature is about 1178° F. and the liquidus temperature is about 1247° F.  
     
     
         5 . A process of using a phosphorus/copper/antimony/tin brazing alloy to produce a brazed joint with a raised shoulder and with little black oxide, comprising the steps of: 
 a) melting an alloy comprising by weight: 
 1. 6.0% to 7.0% phosphorus;  
 2. about 2% to about 8% tin;  
 3. about 2% antimony; and  
 4. the balance copper;  
   b) applying the melted alloy to a joint to be brazed;    c) allowing the melted alloy to cool; and    d) forming a raised shoulder of solidified alloy about the joint without the substantial production of black oxide.    
     
     
         6 . The process of  claim 1 , wherein the percentage of phosphorus is 6.75%.  
     
     
         7 . The process of  claim 1 , wherein the percentage of phosphorus is 6.7% and the percentage of tin is 6%.  
     
     
         8 . The process of  claim 1 , wherein the solidus temperature is about 1178° F. and the liquidus temperature is about 1247° F.