| 摘要 |
The problem to be solved by the present invention is to provide a significant improvement in the properties in Cu—Ni—Co—Si alloy by adding Cr, i.e., to provide Corson alloys having high strength and high electrical conductivity. There is provided a copper alloy for electronic materials comprising 1.0 to 4.5 mass % of Ni, 0.50 to 1.2 mass % of Si, 0.1 to 2.5 mass % of Co, 0.003 to 0.3 mass % of Cr, with the balance being Cu and unavoidable impurities, the mass concentration ratio of the total mass of Ni and Co to Si ([Ni+Co]/Si ratio) satisfies the formula: 4≰[Ni+Co]/Si≰5, and with regard to Cr—Si compound whose size is 0.1 to 5μm dispersed in the material, atomic concentration ratio of Cr to Si in the dispersed particle is 1-5, and area dispersion density thereof is more than 1×104/mm2, and not more than 1×106/mm2. |
