| 摘要 |
A high-strength and high-electrical conductivity copper alloy rolled sheet has an alloy composition containing 0.14 to 0.34 mass% of Co, 0.046 to 0.098 mass% of P, 0.005 to 1.4 mass% of Sn and the balance including Cu and inevitable impurities, in which [Co] mass% representing a Co content and [P] mass% representing a P content satisfy the relationship of 3.0‰¤([Co]-0.007)/([P]-0.009)‰¤5.9. In a metal structure, precipitates are formed, the shape of the precipitates is substantially circular or elliptical, the precipitates are made to have an average grain diameter of 1.5 to 9.0 nm, or 90% or more of all the precipitates are made to have a diameter of 15 nm or less to be fine precipitates, and the precipitates are uniformly dispersed. With the precipitation of the fine precipitates of Co and P and the solid-solution of Sn, the strength, conductivity and heat resistance are improved and a reduction in costs is realized. |
