| 摘要 |
A copper-based alloy casting includes 69 to 88% of Cu, 2 to 5% of Si, 0.0005 to 0.04% of Zr, 0.01 to 0.25% of P by mass, and a remainder including Zn and inevitable impurities, and satisfies 60 <= Cu - 3.5 × Si - 3 × P <= 71. Further, mean grain size after melt-solidification is 100 µm or less, and .alpha., .kappa. and .gamma.-phases occupy more than 80% of phase structure. Furthermore, the copper-based alloy casting according to the invention can further include at least one element selected from a group consisting of 0.001 to 0.2% of Mg, 0.003 to 0.1% of B, 0.0002 to 0.01% of C, 0.001 to 0.2% of Ti and 0.01 to 0.3% of rare earth element. |
