Abstract: A copper alloy having an excellent corrosion cracking resistance and an excellent dezincing resistance consists of: 58 to 66 wt % of copper (Cu); 0.1 to 0.8 wt % of Sn; 0.01 to 0.5 wt % of Si; at least one of 0.3 to 3.5 wt % of lead (Pb), 0.3 to 3.0 wt % of bismuth (Bi), 0.02 to 0.15 wt % of phosphorus (P), 0.02 to 3.0 wt % of nickel (Ni) and 0.02 to 0.6 wt % of iron (Fe) if necessary; and the balance being zinc (Zn) and unavoidable impurities, wherein the proportion of an alpha phase is 80 vol % or more. The apparent content of zinc (Zn) in the copper alloy is in the range of from 34 to 39 wt %.

Abstract: Copper-base alloys are provided that maintain high hot forgeability and cuttability and low-cost feature and which still are improved in resistance to dezincification. The alloys comprise 57-69% of Cu, 0.3-3% of Sn and 0.02-1.5% of Si, all percentages based on weight, with a Si/Sn value in the range of 0.051, and the balance being Zn and incidental impurities.

Abstract: Copper-base alloys are provided that maintain high hot forgeability and cuttability and low-cost feature and which still are improved in resistance to dezincification. The alloys comprise 57-69% of Cu, 0.3-3% of Sn and 0.02-1.5% of Si, all percentages based on weight, with a Si/Sn value in the range of 0.05-1, and the balance being Zn and incidental impurities.