Patent ID: 9455058
Filing Date: 2016-09-27
CPC Classification: C22C,C22F,H01B

Claim Text:
1. A high-strength and high-electrical conductivity copper alloy rolled sheet which has an alloy composition comprising 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 and is manufactured by a manufacturing process including a casting process, a cutting process, a heating process, a hot rolling process, a cold rolling process and a precipitation heat treatment process in this order, wherein a start temperature of the hot rolling process is in the range of 830 to 960° C. to heat and provide a hot-rolled ingot, wherein the hot-rolled ingot is subjected to a cooling step to obtain a solid solution of Co and P and a recrystallized structure having an average grain size of equal to or larger than 6 μm and equal to or smaller than 50 μm, and wherein the cooling step is selected from the group consisting of: (i) wherein the hot-rolled ingot is cooled with a cooling rate of 2° C./sec or greater from a temperature of the hot-rolled ingot subjected to a final pass of the hot rolling process to 350° C., and (ii) wherein the hot-rolled ingot is cooled with a cooling rate of 2° C./sec or greater from 650° C. to 350° C., 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, a total cold rolling ratio is equal to or greater than 70%, after a final precipitation heat treatment process, a recrystallization ratio is equal to or less than 45%, an average grain size of recrystallized grains in a recrystallization portion is in the range of 0.7 to 7 μm and circular or elliptical precipitates are present in a metal structure, the precipitates are fine precipitates of which 90% or greater are equal to or less than 25 nm in diameter, and the precipitates are uniformly dispersed, wherein after the final precipitation heat treatment, the metal structure includes a fibrous metal structure extending in a rolling direction of the metal structure, and in the fibrous metal structure fine crystals are present which have no annealing twin crystals and in which an average long/short ratio, which is observed from an inverse pole figure (IPF) map and a grain boundary map in an EBSP analysis result, is equal to or greater than 2 and equal to or less than 15, and an average grain size of the fine crystals is in the range of 0.3 to 4 μm and a proportion of the area of the fine crystals to the whole metal structure in an observation plane is in the range of 0.1% to 25%.