Phosphorus-copper base brazing alloy

Abstract

A solid phos-copper base brazing alloy component for forming a brazed joint with a raised shoulder and little to no black oxide. The brazing alloys of the present invention are visually distinguishable from copper and copper alloy parts and may provide a good color match for silver and silver alloys, including sterling silver. The solid brazing components of the present invention may be used in forming brazed joints at low brazing temperatures and result in a joint that is ductile, smooth and corrosion resistant. The solid brazing components are provided in the form of wire, strip, foil or a preform, and thus are advantageously used in a wide variety of brazing applications including copper tubing and intricate jewelry. The brazing components of the present invention are made of an alloy having a liquidus temperature above 840° F. and consist essentially of about 4-10% phosphorus, about 0.1-8% tin, up to about 4% antimony, about 0.001-3% silicon, up to about 18% silver, up to about 3% nickel, up to about 3% manganese, with the balance being copper. Exemplary embodiments include about 0.1-18% silver and/or 0.1-3% nickel.

What is claimed is:  
     
         1 . A solid brazing component having a liquidus temperature above 840° F. selected from the group consisting of: wire, strip, foil and preforms, wherein the brazing component is made of an alloy consisting essentially of, in weight percent: 
 (a) about 4-10% phosphorus;  
 (b) about 0.1-8% tin;  
 (c) about 0.001-3% silicon;  
 (d) up to about 3% nickel;  
 (e) up to about 18% silver;  
 (f) up to about 4% antimony;  
 (g) up to about 3% manganese; and the balance copper.  
 
     
     
         2 . The component of  claim 1  wherein the alloy consists essentially of: 
 (e) about 0.1-18% silver.  
 
     
     
         3 . The component of  claim 2  wherein the alloy consists essentially of: 
 (d) about 0.1-3% nickel.  
 
     
     
         4 . The component of  claim 1  wherein the alloy consists essentially of: 
 (d) about 0.1-3% nickel.  
 
     
     
         5 . The component of  claim 1  wherein the brazing component has a liquidus temperature less than about 1300° F. and a solidus temperature less than about 1200° F.  
     
     
         6 . The component of  claim 5  wherein the alloy consists essentially of: 
 (b) about 6-8% tin; and  
 (d) about 1.4-2% nickel.  
 
     
     
         7 . The component of  claim 6  wherein the alloy exhibits a major thermal arrest at a temperature in the range of about 1215-1240° F.  
     
     
         8 . The component of  claim 1  wherein the alloy exhibits a major thermal arrest at a temperature in the range of about 1125-1255° F.  
     
     
         9 . The component of  claim 1  wherein the alloy consists essentially of: 
 (a) about 5-10% phosphorus;  
 (b) about 0.1-6% tin;  
 (c) about 0.001-1% silicon;  
 (f) up to about 2% antimony; and the balance copper.  
 
     
     
         10 . The component of  claim 1  wherein the alloy consists essentially of: 
 (a) about 6-7% phosphorus;  
 (b) about 2-8% tin;  
 (c) about 0.001-1% silicon;  
 (f) up to about 2% antimony; and the balance copper.  
 
     
     
         11 . The component of  claim 10  wherein the alloy exhibits a major thermal arrest at a temperature below about 1275° F.  
     
     
         12 . The component of  claim 2  wherein the alloy consists essentially of: 
 (a) about 6% phosphorus;  
 (b) about 6-7% tin;  
 (c) about 0.02% silicon;  
 (e) about 6-10% silver;  
 (f) up to about 2% antimony; and the balance copper.  
 
     
     
         13 . The component of  claim 3  wherein the alloy consists essentially of: 
 (a) about 5-6% phosphorus;  
 (b) about 6-7% tin;  
 (c) about 0.02% silicon;  
 (d) about 2% nickel;  
 (e) about 15% silver;  
 (f) up to about 2% antimony; and the balance copper.  
 
     
     
         14 . The component of  claim 13  wherein the alloy has a liquidus temperature of about 1260° F. or less.  
     
     
         15 . The component of  claim 2  wherein the alloy consists essentially of: 
 (a) about 6-7% phosphorus;  
 (b) about 2-7% tin;  
 (c) about 0.01-0.1% silicon;  
 (e) about 3% silver;  
 (f) up to about 2% antimony; and the balance copper.  
 
     
     
         16 . The component of  claim 4  wherein the alloy consists essentially of: 
 (a) about 6-7% phosphorus;  
 (b) about 6-7% tin;  
 (c) about 0.01-0.1% silicon;  
 (d) about 1-2% nickel;  
 (f) up to about 2% antimony; and the balance copper, wherein the brazing component has a liquidus temperature less than about 1300° F.  
 
     
     
         17 . The component of  claim 16  wherein the alloy exhibits a major thermal arrest at a temperature in the range of about 1215-1255° F.  
     
     
         18 . The component of  claim 3  wherein the alloy consists essentially of: 
 (a) about 4-7% phosphorus;  
 (b) about 5-7% tin;  
 (c) about 0.01-0.1% silicon;  
 (d) about 1.4-2% nickel;  
 (e) about 5-18% silver;  
 (f) up to about 2% antimony; and the balance copper, wherein the brazing component has a liquidus temperature less than 1300° F. and a solidus temperature of about 1060° F. or less.  
 
     
     
         19 . The component of  claim 18  wherein the alloy exhibits a major thermal arrest at a temperature in the range of about 1125-1160° F.  
     
     
         20 . The component of  claim 18  wherein the alloy has a liquidus temperature in the range of about 1105-1120° F.  
     
     
         21 . A method of forming a brazed joint comprising the steps of: 
 providing a solid brazing component having a liquidus temperature above 840° F. selected from the group consisting of: wire, strip, foil and preforms, wherein the brazing component is made of an alloy consisting essentially of, in weight percent:    (a) about 4-10% phosphorus;    (b) about 0.1-8% tin;    (c) about 0.001-3% silicon;    (d) up to about 3% nickel;    (e) up to about 18% silver;    (f) up to about 4% antimony;    (g) up to about 3% manganese; and the balance copper;    placing the solid brazing component between two metal parts;    heating the solid brazing component to melt at least a major portion of the alloy to cause the alloy to wet and flow between the two metal parts;    cooling the alloy to form a brazed joint with a raised cap between the two metal parts, wherein the brazed joint is substantially free of black metal oxide.    
     
     
         22 . The method of  claim 21  wherein the solid brazing component is placed between two copper or copper alloy parts and the brazed joint is visually distinguishable from the parts.  
     
     
         23 . The method of  claim 21  wherein the solid brazing component is placed between two sterling silver parts and the brazed joint is substantially the same color as the sterling silver.  
     
     
         24 . The method of  claim 21  wherein the solid brazing component is placed between two tubular shaped parts.  
     
     
         25 . The method of  claim 21  wherein the solid brazing component is heated to a temperature less than 1400° F. to melt the major portion.  
     
     
         26 . The method of  claim 21  wherein the solid brazing component is heated to a temperature less than 1300° F. to melt the major portion.  
     
     
         27 . The method of  claim 21  wherein the solid brazing component is heated to a temperature less than 1130° F. to melt the major portion.