Copper alloy containing cobalt, nickel and silicon

Abstract

A process for manufacturing copper-nickel-silicon alloys includes the sequential steps of casting the copper alloy; hot working the cast copper-base alloy to effect a first reduction in cross-sectional area; solutionizing the cast copper-base alloy at a temperature and for a time effective to substantially form a single phase alloy; first age annealing the alloy at a temperature and for a time effective to precipitate an amount of a second phase effective to form a multi-phase alloy having silicides; cold working the multi-phase alloy to effect a second reduction in cross-sectional area; and second age annealing the multiphase alloy at a temperature and for a time effective to precipitate additional silicides thereby raising conductivity, wherein the second age annealing temperature is less than the first age annealing temperature.

1 .- 23 . (canceled) 
     
     
         24 . A process for the manufacture of a copper-base alloy, comprising the sequential steps of: a). casting said copper-base alloy containing, by weight, from 0.5% to 5.0% nickel and 0.1% to 1.5% silicon; b). hot working said cast copper-base alloy to effect a first reduction in cross-sectional area; c). solutionizing said cast copper-base alloy at a solutionizing temperature and for a first time effective to substantially form a single phase alloy; d). without any intervening cold work following said solutionizing, first age annealing said substantially single phase alloy at a first age anneal temperature and for a second time effective to precipitate a second phase; e). cold working said multi-phase alloy to effect a second reduction in cross-sectional area; and f). second age annealing said multiphase alloy at a second age anneal temperature and for a third time effective to precipitate an additional amount of said second phase, wherein said second age anneal temperature is less than said first age anneal temperature. 
     
     
         25 . The process of  claim 24  wherein following said solutionizing step, an average grain size of said wrought copper alloy is 20 microns or less. 
     
     
         26 . The process of  claim 24  including a step of cold working said wrought copper alloy between said hot working step (b) and said solutionizing step (c). 
     
     
         27 . The process of  claim 26  wherein both said hot working step and said cold working steps constitute rolling and said wrought copper alloy is formed into a strip. 
     
     
         28 . A process for the manufacture of a copper-base alloy, comprising the sequential steps of: a). casting said copper-base alloy containing, by weight, from 0.5% to 5.0% nickel and 0.1% to 1.5% silicon; b). hot working said cast copper-base alloy in one or more passes to form a hot worked product; c). solutionizing said hot worked product at a temperature in excess of from 800° C. to a solidus temperature of said copper-base alloy; d). without any intervening cold work following said solutionizing, first age annealing said hot worked plate at a temperature of from 350° C. to 600° C. for from 30 minutes to 30 hours; e). cold working said hot worked plate to a reduction in cross-sectional area of from 10% to 50% to form a product; and f). second age annealing said product at a temperature less than said first precipitation annealing temperature. 
     
     
         29 . The process of  claim 28  wherein said hot working is at a temperature of between 850° C. and 1000° C. and said solutionizing temperature of between 800° C. and 1000° C. 
     
     
         30 . The process of  claim 29  further including a step of quenching said copper base alloy following said hot working step (b). 
     
     
         31 . The process of  claim 30  wherein said first age anneal is at a temperature of between 475° C. and 550° C. and said second age anneal temperature is between 350° C. and 500° C. 
     
     
         32 . The process of  claim 31  further including a step of cold working said copper alloy to a gauge effective for solutionizing between said quench and said solutionizing step (c). 
     
     
         33 . The process of  claim 32  wherein said hot working step and said cold working steps both constitute rolling thereby forming said copper alloy into a strip. 
     
     
         34 . The process of  claim 32  wherein said copper alloy is selected to have a composition of from 1% to 2.5% of nickel, from 0.5% to 2.0% of cobalt, with a total nickel plus cobalt content of from 1.7% to 4.3%, from 0.5% to 1.5% of silicon with a ratio of (Ni+Co)/Si being between 2:1 and 7:1 and the balance copper and inevitable impurities. 
     
     
         35 . The process of  claim 32  wherein said copper alloy is selected to have a composition of from 1% to 2.5% of nickel, from 0.5% to 2.0% of cobalt, with a total nickel plus cobalt content of from 1.7% to 4.3%, from 0.5% to 1.5% of silicon with a ratio of (Ni+Co)/Si being between 2:1 and 7:1, from an amount effective to improve a combination of yield strength and electrical conductivity up to 1.0% of silver, titanium, zirconium and combinations thereof, up to 0.15% of magnesium and the balance copper and inevitable impurities 
     
     
         36 . The process of  claim 32  wherein said copper alloy is selected to have a composition of 2.2%-4.2% nickel, 0.25%-1.2% silicon, 0.05%-0.30% magnesium and the balance copper. 
     
     
         37 . A process for the manufacture of a copper-base alloy, comprising the sequential steps of: a). casting said copper-base alloy containing, by weight, from 0.5% to 5.0% nickel and 0.1% to 1.5% silicon; b). hot working said cast copper-base alloy in one or more passes to form a hot worked product; c). first age annealing said hot worked product at a temperature of from 350° C. to 600° C. for from 30 minutes to 30 hours; d). cold working said hot worked product to a reduction in cross-sectional area of from 10% to 50% to form a product; and e). second age annealing said product at a temperature less than said first precipitation annealing temperature. 
     
     
         38 . The process of  claim 37  wherein said hot working is at a temperature of between 850° C. and 1000° C. 
     
     
         39 . The process of  claim 38  further including a step of quenching said copper base alloy following said hot working step (b). 
     
     
         40 . The process of  claim 39  wherein said first age anneal is at a temperature of between 475° C. and 550° C. and said second age anneal temperature is between 350° C. and 500° C. 
     
     
         41 . The process of  claim 40  wherein said copper alloy is selected to have a composition of from 1% to 2.5% of nickel, from 0.5% to 2.0% of cobalt, with a total nickel plus cobalt content of from 1.7% to 4.3%, from 0.5% to 1% of silicon with a ratio of (Ni+Co)/Si being between 3.5 and 5.5 and the balance copper and inevitable impurities. 
     
     
         42 . The process of  claim 40  wherein said copper alloy is selected to have a composition of from 1% to 2.5% of nickel, from 0.5% to 2.0% of cobalt, with a total nickel plus cobalt content of from 1.7% to 4.3%, from 0.5% to 1.5% of silicon with a ratio of (Ni+Co)/Si being between 2:1 and 7:1, from an amount effective to improve a combination of yield strength and electrical conductivity up to 1.0% of silver, titanium, zirconium and combinations thereof, up to 0.15% of magnesium and the balance copper and inevitable impurities 
     
     
         43 .- 59 . (canceled)