Cu Ni Ni Ni Co a-Si based alloy material and its manufacturing method and an energizing component

PROBLEM TO BE SOLVED : To provide a copper alloy sheet material having stably improved strength, conductivity, bendability and stress relaxation resistance at the same time with a high level even with a sheet thickness of less than 0.15 mm.SOLUTION : There is provided a copper alloy sheet material having a composition containing, by mass%, Ni : 1.0 to 3.5%, Co : 0.5 to 1.0%, Si : 0.35 to 1.25% and the total content of Fe, Cr, Mg, Mn, Ti, V, Zr, Sn, Zn, Al, B, P, Ag and rare earth elements of 0 to 1.0 mass% and the balance Cu with inevitable impurities, with (Ni+Co)/Si mass ratio of 3.4 to 4.2, and the number density of second phase particles having a diameter of 500 nm or more of 10/mmor less.