Copper alloy sheet material and method of producing the same

Abstract

A copper alloy sheet material, having an R value of 1 or greater, which is defined by: R =([ BR]+[RDW]+[W])/([C]+[S]+[B ]) wherein [BR], [RDW], [W], [C], [S], and [B] represent an area ratio of crystal texture orientation component of BR orientation {3 6 2}<8 5 3>, RD-rotated-cube orientation {0 1 2}<1 0 0>, cube orientation {1 0 0}<0 0 1>, copper orientation {1 2 1}<1 1 1>, S-orientation {2 3 1}<3 4 6>, and brass orientation {1 1 0}<1 1 2>, respectively, in crystal orientation analysis in an EBSD (electron back scatter diffraction) analysis, and having a proof stress of 500 MPa or greater, and an electrical conductivity of 30%IACS or higher; and a production method of the same.

1 - 7 . (canceled) 
     
     
         8 . A copper alloy sheet material, having an alloy composition containing any one or two of Ni and Co 0.5 to 5.0 mass % in total, Si 0.1 to 1.5 mass %, and optionally at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Fe, Ti, Zr, and Hf 0.005 to 2.0 mass % in total, with the balance being copper and unavoidable impurities,
 having an R value of 1 or greater, which is defined by:
     R =([ BR]+[RDW]+[W ])/([ C]+[S]+[B ]) 
   wherein [BR], [RDW], [W], [C], [S], and [B] represent an area ratio of crystal texture orientation component of BR orientation {3 6 2}<8 5 3>, RD-rotated-cube orientation {0 1 2}<1 0 0>, cube orientation {1 0 0}<0 0 1>, copper orientation {1 2 1}<1 1 1>, S-orientation {2 3 1}<3 4 6>, and brass orientation {1 1 0}<1 1 2>, respectively, in crystal orientation analysis in an EBSD (electron back scatter diffraction) analysis, and having a proof stress of 500 MPa or greater, and an electrical conductivity of 30%IACS or higher.   
     
     
         9 . A connector, which is composed of the copper alloy sheet material according to  claim 8 . 
     
     
         10 . A method of producing the copper alloy sheet material according to  claim 8 , comprising the steps of: subjecting a copper alloy having the alloy composition to give the copper alloy, to casting [Step 1], a homogenization heat treatment [Step 2], hot-working [Step 3], cold-rolling [Step 6], a heat treatment [Step 7], cold-rolling [Step 8], and a final solution heat treatment [Step 9], in this order, and then subjecting the resultant copper alloy to an aging precipitation heat treatment [Step 10], BIRCH, STEWART, KOLASCH & BIRCH, LLP MSW/CAM/kec
 wherein the hot-working [Step 3] is carried out, by first conducting two or more passes of hot-rolling at a temperature from (P+30)° C. to 1,020° C. (in which P (° C.) represents the complete solid solution temperature of solute atoms) at a working ratio per pass of 25% or higher, cooling to a temperature (P−30)° C. or lower, and then conducting two or more passes of hot-rolling at a temperature from 400° C. to (P−30)° C. at a working ratio per pass of 25% or lower, wherein the cold-rolling [Step 6] is carried out at a working ratio of 50 to 99%, wherein the heat treatment [Step 7] is carried out by maintaining at 600 to 900° C. for 10 seconds to 5 minutes, and wherein the cold-working [Step 8] is carried out at a working ratio of 5 to 55%. 
 
     
     
         11 . The method of producing the copper alloy sheet material according to  claim 10 , wherein cold-rolling [Step 11] and temper annealing [Step 12] are conducted in this order, after the aging precipitation heat treatment [Step 10].