| 摘要 |
PROBLEM TO BE SOLVED: To provide a Cu-Zn-Sn-Ni-P-based alloy which includes at least 3 mass% of Zn whose raw material cost is inexpensive compared to Cu and Ni, allows containing of Sn incorporated in copper scraps, has low cost, is simultaneously excellent in strength, bendability, and stress relaxation resistance characteristics, and has little anisotropy.SOLUTION: A Cu-Zn-Sn-Ni-P-based alloy includes, by mass, 0.2-0.8% of Sn, 3-18% of Zn, 0.3-1.2% of Ni, and 0.01-0.12% of P, with the balance comprising Cu and unavoidable impurities, wherein a grain size ratio a/b is 0.9-1.4 when the grain size in the direction parallel to the rolling direction is a, and the grain size in the direction perpendicular to the rolling direction is b, and a number density of a particle of a Ni-P-based compound in a cross-sectional surface in the direction parallel to the rolling direction is in the following range: (1) the particle A of the Ni-P-based compound of at least 2.0 μm is 10 pieces/mm2 or less; and (2) the particle B of the Ni-P-based compound of 100-500 nm is 50-500 pieces/mm2. |
