High-strength, high-conductivity copper alloy wire excellent in resistance to stress relaxation

Abstract

A high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, which contains 1.0 to 4.5% by mass of Ni, 0.2 to 1.1% by mass of Si, 0.05 to 1.5% by mass of Sn, and less than 0.005% (including zero) by mass of S, with the balance being Cu and inevitable impurities, wherein the wire has a conductivity of from 20% to 60% IACS and a tensile strength of from 700 to 1,300 MPa, and a method of producing the same.

1 . A high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising 1.0 to 4.5% by mass of Ni, 0.2 to 1.1% by mass of Si, 0.05 to 1.5% by mass of Sn, and less than 0.005% (including zero) by mass of S, with the balance being Cu and inevitable impurities, wherein the wire has a conductivity of from 20% to 60% IACS, and a tensile strength of from 700 to 1,300 MPa.  
     
     
         2 . A high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising 1.0 to 4.5% by mass of Ni, 0.2 to 1.1% by mass of Si, 0.05 to 1.5% by mass of Sn, 0.2 to 1.5% by mass of Zn, and less than 0.005% (including zero) by mass of S, with the balance being Cu and inevitable impurities, wherein the wire has a conductivity of from 20% to 60% IACS, and a tensile strength of from 700 to 1,300 MPa.  
     
     
         3 . A high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation according to  claim 1  or  2 , further containing at least one or plural elements selected from the group consisting of 0.005 to 0.3% by mass of Ag, 0.01 to 0.5% by mass of Mn, 0.01 to 0.2% by mass of Mg, 0.005 to 0.2% by mass of Fe, 0.005 to 0.2% by mass of Cr, 0.05 to 2% by mass of Co, and 0.005 to 0.1% by mass of P in a total amount of 0.005 to 2% by mass, wherein the wire has a conductivity of from 20% to 60% IACS, and a tensile strength of from 700 to 1,300 MPa.  
     
     
         4 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing a copper alloy comprising 1.0 to 4.5% by mass of Ni, 0.2 to 1.1% by mass of Si, 0.05 to 1.5% by mass of Sn, and less than 0.005% (including zero) by mass of S, with the balance being Cu and inevitable impurities, to form a wire rod;    subjecting the wire rod to a solution treatment; and    subjecting the wire rod to at least one step selected from an aging treatment and drawing, thereby obtaining a copper alloy wire having a conductivity of from 20% to 60% IACS and a tensile strength of from 700 to 1,300 MPa.    
     
     
         5 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing a copper alloy comprising 1.0 to 4.5% by mass of Ni, 0.2 to 1.1% by mass of Si, 0.05 to 1.5% by mass of Sn, 0.2 to 1.5% by mass of Zn, and less than 0.005% (including zero) by mass of S, with the balance being Cu and inevitable impurities, to form a wire rod;    subjecting the wire rod to a solution treatment; and    subjecting the wire rod to at least one step selected from an aging treatment and drawing, thereby obtaining a copper alloy wire having a conductivity of from 20% to 60% IACS and a tensile strength of from 700 to 1,300 MPa.    
     
     
         6 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , further containing at least one or plural elements selected from the group consisting of 0.005 to 0.3% by mass of Ag, 0.01 to 0.5% by mass of Mn, 0.01 to 0.2% by mass of Mg, 0.005 to 0.2% by mass of Fe, 0.005 to 0.2% by mass of Cr, 0.05 to 2% by mass of Co, and 0.005 to 0.1% by mass of P, in a total amount of 0.005 to 2% by mass, to form a wire rod;    subjecting the wire rod to a solution treatment; and    subjecting the wire rod to at least one step selected from an aging treatment and drawing, thereby obtaining a copper alloy wire having a conductivity of from 20% to 60% IACS and a tensile strength of from 700 to 1,300 MPa.    
     
     
         7 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment;    drawing the wire rod at a reduction ratio of from 0 to 4, aging at from 400° C. to 550° C. for 1.5 hours or more; and    drawing at a reduction ratio of 3 or more, thereby obtaining a copper alloy wire having a tensile strength of 1,000 MPa or more and a conductivity of 20% IACS or more.    
     
     
         8 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment;    drawing the wire rod at a reduction ratio of from 0 to 4, aging at from 400° C. to 550° C. for 1.5 hours or more;    drawing at a reduction ratio of 3 or more; and    annealing at from 350° C. to 500° C. for 1.5 hours or more, thereby obtaining a copper alloy wire having a conductivity of 40% IACS or more and a tensile strength of 700 MPa or more.    
     
     
         9 . A method for producing a high-strength,high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment; and    drawing the wire rod at a reduction ratio of 7 or more, thereby obtaining a copper alloy wire having a tensile strength of 1,000 MPa or more and a conductivity of 20% IACS or more.    
     
     
         10 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment;    drawing at a reduction ratio of 7 or more; and    annealing at a temperature of from 200° C. to 400° C. for 1.5 hours or more, thereby obtaining a copper alloy wire having a tensile strength of 1,000 MPa or more and a conductivity of 20% IACS or more.    
     
     
         11 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment;    drawing at a reduction ratio of 3 or more;    aging at from 400° C. to 600° C. for 1.5 hours or more; and    drawing at a reduction ratio of from 0 to less than 3, thereby obtaining a copper alloy wire having a conductivity of 40% IACS or more and a tensile strength of 700 MPa or more.    
     
     
         12 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment; drawing at a reduction ratio of from 0.7 to 4;    aging at from 400° C. to 600° C. for 1.5 hours or more; and    drawing at a reduction ratio of less than 6, thereby obtaining a copper alloy wire having a tensile strength of from 900 to 1100 MPa and a conductivity of from 30% to 45% IACS.    
     
     
         13 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment;    drawing at a reduction ratio of from 0 to 4;    aging at from 400° C. to 600° C. for 1.5 hours or more;    repeating a set of steps (I) and (II) twice or more, in which step (I) is a step of drawing at a reduction ratio of exceeding 0 and 4 or less, and step (II) after step (I) is a step of annealing at a temperature lower than the first aging temperature in a range of 300° C. to 550° C. for 1.5 hours or more; and    drawing at a reduction ratio of from 0 to 4, thereby obtaining a copper alloy wire having a tensile strength of from 900 to 1100 MPa and a conductivity of from 30% to 45% IACS.    
     
     
         14 . A method for producing a high-strength, high-conductivity copper alloy wire that is excellent in resistance to stress relaxation, comprising: 
 rough drawing the copper alloy according to  claim 1  or  2 , to form a wire rod;    subjecting the wire rod to a solution treatment; and    aging at from 400° C. to 600° C. for 1.5 hours or more, thereby obtaining a copper alloy wire having a tensile strength of from 700 to 1100 MPa and a conductivity of from 20% to 50% IACS.