| 摘要 |
A copper alloy sheet for terminal and connector materials contains 4.5 mass % to 12.0 mass % of Zn, 0.40 mass % to 0.9 mass % of Sn, 0.01 mass % to 0.08 mass % of P, and 0.20 mass % to 0.85 mass % of Ni with a remainder being Cu and inevitable impurities, a relationship of 11≦[Zn]+7.5×[Sn]+16×[P]+3.5×[Ni]≦19 is satisfied, a relationship of 7≦[Ni]/[P]≦40 is satisfied in a case in which the content of Ni is in a range of 0.35 mass % to 0.85 mass %, an average crystal grain diameter is in a range of 2.0 μm to 8.0 μm, an average particle diameter of circular or elliptical precipitates is in a range of 4.0 nm to 25.0 nm or a proportion of the number of precipitates having a particle diameter in a range of 4.0 nm to 25.0 nm in the precipitates is 70% or more, an electric conductivity is 29% IACS or more, a percentage of stress relaxation is 30% or less at 150° C. for 1000 hours as stress relaxation resistance, bending workability is R/t≦0.5 at W bending, solderability is excellent, and a Young's modulus is 100×103 N/mm2 or more. |
