This free-cutting copper alloy includes Cu: more than 58.0% and less than 65.0%, Si: more than 0.30% and less than 1.30%, Pb: more than 0.001% and 0.20% or less, Bi: more than 0.020% and 0.10% or less, and P: more than 0.001% and less than 0.20%, with the remainder being Zn and unavoidable impurities, a total amount of Fe, Mn, Co and Cr is less than 0.45%, a total amount of Sn and Al is less than 0.45%, relationships of 56.5≤[Cu]−4.7×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5, and 0.025≤[Pb]+[Bi]<0.25 are satisfied, in constituent phases of a metallographic structure, relationships of 20≤(α)<85, 15<(β)≤80, 0≤(γ)<5, 8.0≤([Bi]+[Pb]−0.002).sup.1/2×10+([P]−0.001).sup.1/2×5+((β)−7).sup.1/2×([Si]−0.1).sup.1/2×1.2+(γ).sup.1/2×0.5≤17.0, and 0.9≤([Bi]+[Pb]−0.002).sup.1/2×((β)−7).sup.1/2×([Si]−0.1).sup.1/2≤4.0 are satisfied, and a particle containing Bi is present in α phase.

This free-cutting copper alloy includes Cu: more than 58.0% and less than 65.0%, Si: more than 0.30% and less than 1.30%, Pb: more than 0.001% and 0.20% or less, Bi: more than 0.020% and 0.10% or less, and P: more than 0.001% and less than 0.20%, with the remainder being Zn and unavoidable impurities, a total amount of Fe, Mn, Co and Cr is less than 0.45%, a total amount of Sn and Al is less than 0.45%, relationships of 56.5≤[Cu]−4.7×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5, and 0.025≤[Pb]+[Bi]<0.25 are satisfied, in constituent phases of a metallographic structure, relationships of 20≤(α)<85, 15<(β)≤80, 0≤(γ)<5, 8.0≤([Bi]+[Pb]−0.002).sup.1/2×10+([P]−0.001).sup.1/2×5+((β)−7).sup.1/2×([Si]−0.1).sup.1/2×1.2+(γ).sup.1/2×0.5≤17.0, and 0.9≤([Bi]+[Pb]−0.002).sup.1/2×((β)−7).sup.1/2×([Si]−0.1).sup.1/2≤4.0 are satisfied, and a particle containing Bi is present in α phase.

The invention is a copper alloy with excellent comprehensive performance, including the following components in percentage by weight: 0.4 wt %-2.0 wt % of Ni, 0.2 wt %-2.5 wt % of Sn, 0.02 wt %-0.25 wt % of P, 0.001 wt %-0.5 wt % of Si, and the balance of Cu and unavoidable impurities. The copper alloy has a yield strength of 550 MPa or above, and an electrical conductivity of 38% IACS or above. A bending workability is as follows: the value of R/t in the GW direction is less than or equal to 1, and the value of R/t in the BW direction is less than or equal to 2; and after the copper alloy is kept at 150° C. for 1000 hours, a residual stress rate is greater than or equal to 75%, and the stress relaxation resistance is excellent.

The present invention relates to a method for producing metal-comprising geometrically complex pieces and/or parts. The method is specially indicated for highly performant components. It is disclosed a method for the production of complex geometry, and even large, highly performant metal-comprising components in a cost effective way. The method is also indicated for the construction of components with internal features and voids. The method is also beneficial for light construction. The method allows the reproduction of bio-mimetic structures and other advanced structures for topological performance optimization.

This free-cutting copper alloy contains Cu: more than 57.5% but less than 64.5%, Si: more than 0.20% but less than 1.20%, Pb: more than 0.001% but less than 0.20%, Bi: more than 0.10% but less than 1.00%, and P: more than 0.001% but less than 0.20%, with the balance being Zn and unavoidable impurities, wherein the total amount of Fe, Mn, Co and Cr is less than 0.45%, the total amount of Sn and Al is less than 0.45%, relationships of 56.3≤f1=[Cu]−4.8×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5 and 0.12≤f2=[Pb]+[Bi]<1.0 are satisfied.

This free-cutting copper alloy includes Cu: more than 61.0% and less than 65.0%, Si: more than 1.0% and less than 1.5%, Pb: 0.003% to less than 0.20%, and P: more than 0.003% and less than 0.19%, with the remainder being Zn and unavoidable impurities, a total content of Fe, Mn, Co, and Cr is less than 0.40%, a total content of Sn and Al is less than 0.40%, a relationship of 56.5≤f1=[Cu]−4.5×[Si]+0.5×[Pb]−[P]≤59.5 is satisfied, constituent phases of a metallographic structure have relationships of 20≤(α)≤80, 15≤(β)≤80, 0≤(γ)<8, 18×(γ)/(β)<9, 20≤(γ).sup.1/2×3+(β)×([Si]).sup.1/2≤88, and 33≤(γ).sup.1/2×3+(β)×([Si]).sup.1/2+([Pb]).sup.1/2×35+([P]).sup.1/2×15, and a compound including P is present in β phase.

This copper alloy casting includes, in terms of mass %: Cu: higher than 58.5% and lower than 65.0%; Si: higher than 0.40% and lower than 1.40%; Pb: higher than 0.002% and lower than 0.25%; P: higher than 0.003% and lower than 0.19%; and Bi: 0.001% to 0.100% as an optional element, with the balance being Zn and inevitable impurities, the total content of Fe, Mn, Co, and Cr is lower than 0.45% and the total content of Sn and Al is lower than 0.45%, a relationship of 56.0≤f1=[Cu]−5×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5 is satisfied, when Bi is included, a relationship of 0.003<f0=[Pb]+[Bi]<0.25 is further satisfied.

This copper alloy casting includes, in terms of mass %: Cu: higher than 58.5% and lower than 65.0%; Si: higher than 0.40% and lower than 1.40%; Pb: higher than 0.002% and lower than 0.25%; P: higher than 0.003% and lower than 0.19%; and Bi: 0.001% to 0.100% as an optional element, with the balance being Zn and inevitable impurities, the total content of Fe, Mn, Co, and Cr is lower than 0.45% and the total content of Sn and Al is lower than 0.45%, a relationship of 56.0≤f1=[Cu]−5×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5 is satisfied, when Bi is included, a relationship of 0.003<f0=[Pb]+[Bi]<0.25 is further satisfied.

This free-cutting copper alloy contains Cu: more than 57.5% but less than 64.5%, Si: more than 0.20% but less than 1.20%, Pb: more than 0.001% but less than 0.20%, Bi: more than 0.10% but less than 1.00%, and P: more than 0.001% but less than 0.20%, with the balance being Zn and unavoidable impurities, wherein the total amount of Fe, Mn, Co and Cr is less than 0.45%, the total amount of Sn and Al is less than 0.45%, relationships of 56.3≤f1=[Cu]−4.8×[Si]+0.5×[Pb]+0.5×[Bi]−0.5×[P]≤59.5 and 0.12≤f2=[Pb]+[Bi]<1.0 are satisfied.

The negative electrode active material according to the present embodiment includes alloy particle containing an alloy component and oxygen of 0.50 to 3.00 mass %. The alloy component contains Sn: 13.0 to 40.0 at % and Si: 6.0 to 40.0 at %. The alloy particle contains: one or two phases selected from a D0.sub.3 phase in which the Si content is from 0 to 5.0 at % and a δ phase in which the Si content is from 0 to 5.0 at %; one or two phases selected from an ε phase in which the Si content is from 0 to 5.0 at % and an η′ phase in which the Si content is from 0 to 5.0 at %; and an SiOx phase. The alloy particle has, in an X-ray diffraction profile, a peak having a largest integrated diffraction intensity in a range of 42.0 to 44.0 degrees of a diffraction angle 2θ.