Copper alloy for heat exchanger tube

Abstract

An alloy comprising copper, nickel, tin and, optionally, phosphorus which can be used in, for example, a copper alloy tube for heat exchangers that provides excellent fracture strength and processability for reducing the weight of the tube and for use in high pressure applications with cooling media such as carbon dioxide.

What is claimed is: 
     
         1 . A copper alloy for use in a heat exchanger, comprising:
 a) nickel at from 0.2% to 1.0% by weight; and   b) tin at from 0.2% to 1.0% by weight;   wherein the remainder of the alloy is copper and impurities.   
     
     
         2 . The alloy of  claim 1 , wherein nickel is present in the alloy at from 0.3% to 0.7% by weight, and wherein the tin is present in the alloy at from 0.3% to 0.7% by weight. 
     
     
         3 . The alloy of  claim 1 , wherein the nickel is present in the alloy at 0.5% by weight, and wherein the tin is present in the alloy at 0.5% by weight. 
     
     
         4 . The alloy of  claim 1 , further comprising phosphorus at from 0.01% to 0.07% by weight. 
     
     
         5 . The alloy of  claim 4 , wherein the phosphorus is present in the alloy at 0.020% by weight. 
     
     
         6 . The alloy of  claim 1 , wherein the alloy has a grain size of from 1 micron to 50 microns. 
     
     
         7 . The alloy of  claim 6 , wherein the alloy has a grain size of 10 microns to 25 microns. 
     
     
         8 . An ACR tube for use in a heat exchanger, wherein the tube comprises a copper alloy comprising:
 a) nickel at from 0.2% to 1.0% by weight; and   b) tin at from 0.2% to 1.0% by weight;   wherein the remainder of the alloy is copper and impurities.   
     
     
         9 . The ACR tube of  claim 8 , wherein nickel is present at from 0.3% to 0.7% by weight, and wherein the tin is present at from 0.3% to 0.7% by weight. 
     
     
         10 . The ACR tube  claim 8 , wherein the nickel is present at 0.5% by weight, and wherein the tin is present at 0.5% by weight. 
     
     
         11 . The ACR tube of  claim 8 , wherein the alloy further comprises phosphorus, wherein the phosphorus is present in the alloy at from 0.01 to 0.07% by weight. 
     
     
         12 . The ACR tube of  claim 11 , wherein the phosphorus is present in the alloy at 0.020% by weight. 
     
     
         13 . The ACR tube of  claim 8 , wherein the alloy has a grain size of from 1 micron to 50 microns. 
     
     
         14 . The ACR tube  claim 13 , wherein the alloy has a grain size of 10 microns to 25 microns. 
     
     
         15 . The ACR tube of  claim 8 , wherein the tube has an outer diameter of from 0.100 inch to 1 inch. 
     
     
         16 . The ACR tube of  claim 8 , wherein the tube has a wall thickness of from 0.004 inch to 0.040 inch. 
     
     
         17 . The ACR tube of  claim 8 , wherein a wall thickness of the tube is minimized relative to a wall thickness of a standard C122 tube to reduce total material cost, and wherein each of the tube and the standard C122 tube exhibit substantially a same burst pressure. 
     
     
         18 . The ACR tube of  claim 17 , wherein the wall thickness of the tube is at least 10% less than the wall thickness of the standard C122 tube.