Patent ID: 10311991

Abstract:
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, wherein [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 have an average grain diameter of 1.5 to 9.0 nm, or 90% or more of all the precipitates 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.