| 摘要 |
PROBLEM TO BE SOLVED: To provide a copper alloy excellent in stress relaxation performance and high strength, and excellent various properties such as bendability and conductivity as a Cu-Zn-Sn based copper alloy for an electronic and electrical equipment electroconductive component such as a connector and other terminal materials.SOLUTION: A copper alloy contains Zn of over 2 mass% and less than 23 mass%, Sn of 0.1 mass% or more and 0.9 mass% or less, Ni of 0.05 mass% or more and less than 1.0 mass%, Fe of 0.001 mass% or more and less than 0.10 mass%, P of 0.005 mass% or more and 0.1 mass% or less and the balance Cu with inevitable impurities, satisfies, by atom ratio, 0.002≤Fe/Ni<1.5, 3<(Ni+Fe)/P<15 and 0.3<Sn/(Ni+Fe)<5, and has tilt grain boundary of an α phase and the subgrain boundary of 80% or less in the Partition Fraction, and an average crystal particle diameter in a range of 0.1 μm or more and 50 μm or less. |
