Patent ID: 9039964
Filing Date: 2015-05-26
Classification: B21B,C22C,C22F,H01B

Abstract:
1. A copper alloy sheet that is produced by a production process including a finish cold rolling process at which a copper alloy material is cold-rolled, wherein an average grain size of the copper alloy sheet is 2.0 μm to 8.0 μm, circular or elliptical precipitates are present in the copper alloy sheet, and an average particle size of the precipitates is 4.0 nm to 25.0 nm, or a percentage of the number of precipitates having a particle size of 4.0 nm to 25.0 nm makes up 70% or more of the precipitates, the copper alloy sheet contains: 4.5% by mass to 12.0% by mass of Zn; 0.40% by mass to 0.90% by mass of Sn; 0.01% by mass to 0.08% by mass of P; and either one or both of 0.005% by mass to 0.08% by mass of Co and 0.03% by mass to 0.85% by mass of Ni; with the remainder being Cu and unavoidable impurities, and [Zn], [Sn], [P], [Co], and [Ni] satisfy a relationship of 11≦[Zn]+7×[Sn]+15×[P]+12×[Co]+4.5×[Ni]≦17, wherein [Zn], [Sn], [P], [Co], and [Ni] represent the contents (% by mass) of Zn, Sn, P, Co, and Ni, respectively.