Copper alloy and copper alloy manufacturing method

Abstract

An object of the present invention is to provide copper alloy which has a dimensionless performance index value M satisfying an inequality: M>400 in either a binary system alloy composition containing Cu and Zr, or a ternary system alloy composition containing Cu, Zr, and B. In the copper alloy of the present invention, a composition by atomic percent is expressed by a composition formula: Cu 100−(a+b) Zr a B b , and a dual phase structure having a layered structure including a plurality of Cu matrices constituted by grain particles and an eutectic phase constituted by the Cu matrix and any of a Cu—Zr compound and a Cu—Zr—B compound is constituted. Part of each of the grain particles contacts other grain particles, and the “a”, the “b”, and the “(a+b)” satisfy 0.05≦a≦8.0, 0≦b≦4.0, and a+b≦8.0.

1 . A copper alloy in which a composition by atomic percent is expressed by a composition formula: Cu 100−(a+b) Zr a B b ; 
 a dual phase structure having a layered structure including a plurality of Cu matrices constituted by grain particles and an eutectic phase, and wherein    at least part of each of said grain particles contacts other grain particles;    said eutectic phase is constituted by said Cu matrices and any of a Cu—Zr compound and a Cu—Zr—B compound is constituted; and    the “a”, the “b” and the “(a+b)” satisfy 0.05≦a≦8.0, 0≦b≦4.0, and a+b≦8.0.    
     
     
         2 . The copper alloy according to  claim 1 , wherein an average diameter of said grain particles is about 10 μm or less.  
     
     
         3 . The copper alloy according to  claim 1 , wherein in said dual phase structure, a precipitation containing at least one of a Cu—Zr compound, a Cu—B compound and a Cu—Zr—B compound is dispersed in said grain particles.  
     
     
         4 . The copper alloy according to  claim 2 , wherein in said dual phase structure, a precipitation containing at least one of a Cu—Zr compound, a Cu—B compound and a Cu—Zr—B compound is dispersed in said grain particles.  
     
     
         5 . A method of manufacturing the copper alloy according to  claim 1 , comprising the steps of: 
 melting and casting said copper alloy by a nonrefractory melting method; and    performing a cold working with a reduction of about 50% or more for said copper alloy.    
     
     
         6 . A method of manufacturing the copper alloy according to  claim 2 , comprising the steps of: 
 melting and casting said copper alloy by a nonrefractory melting method; and    performing a cold working with a reduction of about 50% or more for said copper alloy.    
     
     
         7 . A method of manufacturing the copper alloy according to  claim 3 , comprising the steps of: 
 melting and casting said copper alloy by a nonrefractory melting method; and    performing a cold working with a reduction of 50% or more for said copper alloy.    
     
     
         8 . The method of manufacturing a copper alloy according to  claim 5 , the method further comprising the step of: 
 performing a thermal treatment for 1 to 5 hours at a temperature in a range from 550 to 800° C. immediately before the step of performing said cold working.    
     
     
         9 . The method of manufacturing a copper alloy according to  claim 6 , the method further comprising the step of: 
 performing a thermal treatment for 1 to 5 hours at a temperature in a range from 550 to 800° C. immediately before the step of performing said cold working.    
     
     
         10 . The method of manufacturing a copper alloy according to  claim 7 , the method further comprising the step of: 
 performing a thermal treatment for 1 to 5 hours at a temperature in a range from 550 to 800° C. immediately before the step of performing said cold working.    
     
     
         11 . The method of manufacturing the copper alloy according to  claim 5 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.    
     
     
         12 . The method of manufacturing the copper alloy according to  claim 6 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.    
     
     
         13 . The method of manufacturing the copper alloy according to  claim 7 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.    
     
     
         14 . The method of manufacturing the copper alloy according to  claim 8 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.    
     
     
         15 . The method of manufacturing the copper alloy according to  claim 9 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.    
     
     
         16 . The method of manufacturing the copper alloy according to  claim 10 , the method further comprising the step of: 
 performing an ageing treatment for 1 to 10 hours at a temperature in a range from 300 to 500° C. after the step of performing said cold working.