Copper alloy material, and method for production thereof

Abstract

A copper alloy material according to the present invention is characterized in that the copper alloy material includes: an element X between 0.1% and 4% by mass, in which the element X represents one transition element or not less than two elements selected from Ni, Fe, Co and Cr; an element Y between 0.01% and 3% by mass, in which the element Y represents one element or not less than two elements selected from Ti, Si, Zr and Hf; and a remaining portion to be comprised of copper and an unavoidable impurity, wherein the copper alloy material has an electrical conductivity of not less than 50% IACS, an yield strength of not less than 600 MPa, and a stress relaxation rate of not higher than 20% as to be measured after the same is maintained for 1000 hours at a state under applying a stress of 80% of the yield strength.

1 . A copper alloy material, comprising:
 an element X between 0.1% and 4% by mass, said element X including one or more than two of Ni, Fe, Co and Cr;   an element Y between 0.01% and 3% by mass, said element Y including one or more than two of Ti, Si, Zr and Hf; and   a remaining portion formed of copper and an unavoidable impurity,   wherein said copper alloy material has an electrical conductivity of not less than 50% IACS, an yield strength of not less than 600 MPa, and a stress relaxation rate of not higher than 20% after a stress of 80% of the yield strength is applied for 1000 hours.   
   
   
       2 . The copper alloy material according to  claim 1 , further comprising an element Z between 0.01% and 3% by mass, said element Z including one or more than two of Sn, Mg, Zn, Ag, Mn, B and P. 
   
   
       3 . The copper alloy material as defined in  claim 1 , wherein said copper alloy material has an average crystalline grain diameter not larger than 10 μm. 
   
   
       4 . The copper alloy material according to  claim 1 , further comprising a second phase having a particle diameter between 50 nm and 1000 nm and a distribution density not lower than 104 pieces per mm 2 . 
   
   
       5 . The copper alloy material according to  claim 4 , wherein said second phase is formed of a chemical compound including at least one of Si, Co, Ni, Fe, Ti, Zr and Cr. 
   
   
       6 . The copper alloy material according to  claim 5 , wherein said second phase is formed of the chemical compound including three elements. 
   
   
       7 . A method for production of the copper alloy material according to  claim 1 , comprising the step of:
 applying a process on a copper alloy material, said process sequentially including casting (1), homogenizing heat treatment (2), hot working (3), facing (4), cold working (6), solution heat treatment (7), cold working (9), aging precipitation heat treatment (10), cold working (11), and refining annealing heat treatment (12),   wherein a sum of a processing rate R1(%) in the cold working (9) and a processing rate R2(%) in the cold working (11) is between 5% and 65%.   
   
   
       8 . A method for production of the copper alloy material for an electronic/electrical device according to  claim 1 , comprising the step of:
 applying a process on a copper alloy raw material, said process sequentially including casting (1), homogenizing heat treatment (2), hot working (3), facing (4), cold working (6), solution heat treatment (7), aging precipitation heat treatment (8), cold working (9), aging precipitation heat treatment (10), cold working (11), and refining annealing heat treatment (12),   wherein a sum of a processing rate R1(%) in the cold working (9) and a processing rate R2(%) in the cold working (11) is between 5% and 65%, a treatment temperature in the aging precipitation heat treatment (8) is between 400° C. and 700° C., and a treatment temperature in the aging precipitation heat treatment (10) is lower than the treatment temperature in the aging precipitation heat treatment (8).   
   
   
       9 . The method for production of the copper alloy material for an electronic/electrical device according to  claim 7 , wherein said process further includes aging precipitation heat treatment (5) at a temperature between 400° C. and 800° C. for between five seconds and twenty hours after the facing (4), said cold working (6) being performed thereafter.