Copper alloy sheet material and method for producing copper alloy sheet material

A method for producing a copper alloy sheet material, comprising the successive steps of:

• melting and casting a raw material of a copper alloy comprising 0.5 to 2.5% by mass of Ni, 0.5 to 2.5% by mass of Co, 0.30 to 1.2% by mass of Si, and 0.0 to 0.5% by mass of Cr, the balance being Cu and unavoidable impurities;
• hot-rolling the material while lowering the temperature from 950° C. to 400° C.;
• cold-rolling the material at a rolling rate of 30% or more;
• pre-annealing the material by carrying out a heat treatment for the purpose of deposition, at a heating temperature of 350 to 500° C. for 5.0 to 9.5 hours (calculation formula (Equation 2):
• t=38.0×exp (−0.004 K) is satisfied between the time of the pre-annealing step (t) and a temperature K (° C.);
• cold-rolling the material at a rolling rate of 70% or more;
• solutionizing the material at a heating temperature of 700 to 980° C.;
• aging-treating the material at 350 to 600° C.;
• and
• finish-cold-rolling the material at a rolling rate of 10% or more and 40% or less,
• wherein the producing conditions are adjusted such that calculation formula (Equation 3):
• K=4.5×(I {200}/I0 {200}×exp (0.049a)+76.3) is satisfied among a degree of processing a in the finish cold rolling step, I {200}/I0 {200} after the finish cold rolling step, and a temperature K (° C.) in the pre-annealing step.