Copper alloy strip exhibiting improved dimensional accuracy after press-working
Provided is a Corson alloy having improved bending workability and also having high dimensional accuracy after press-working. A copper alloy strip which is a rolling material, the rolling material containing from 0 to 5.0% by mass of Ni or from 0 to 2.5% by mass of Co, the total amount of Ni+Co being from 0.2 to 5% by mass; from 0.2 to 1.5% by mass of Si, the balance being copper and unavoidable impurities, wherein the rolling material satisfies the relationship: A 0 /A≤1.000, in which A 0 represents a projected area of an indentation remaining after carrying out a Vickers hardness test by maintaining a square pyramidal indenter for 10 seconds while applying a test force with a load of 1 kg to a surface of a base material and releasing the test force; and A represents an area connecting vertices of the indenter, and wherein the rolling material satisfies the relationship: 0.1≤I (200) /I 0(200) <1.0, in which I (200) represents an X-ray diffraction intensity from a (200) plane on the surface, and I 0(200) represents an X-ray diffraction intensity from a (200) plane of a pure copper powder standard sample.
1. A copper alloy rolled material strip, the rolled material strip containing (i) one or both of Ni and Co, where the Ni is from 0 to 5.0% by mass and the Co is from 0 to 2.5% by mass, and wherein the total amount of Ni+Co being from 0.2 to 5% by mass; (ii) from 0.2 to 1.5% by mass of Si, and (iii) the balance being copper and unavoidable impurities,
wherein the rolled material strip satisfies the relationship: A 0 /A≤1.000, in which A 0 represents a projected area of an indentation remaining after carrying out a Vickers hardness test by maintaining a square pyramidal indenter for 10 seconds while applying a test force with a load of 1 kg to a surface of a base material and releasing the test force; and A represents an area connecting vertices of the indenter, and
wherein the rolled material strip satisfies the relationship: 0.1≤I (200) /I 0(200) <1.0, in which I (200) represents an X-ray diffraction intensity from a (200) plane on the surface, and I 0(200) represents an X-ray diffraction intensity from a (200) plane of a pure copper powder standard sample.
2. The copper alloy strip according to claim 1 , wherein the copper strip has an rolled surface, and wherein an average grain size of a rolled surface is from 2 to 20 μm, as determined by a cutting method.
3. The copper alloy strip according to claim 1 , wherein the copper alloy strip further contains one or more of Sn, Zn, Mg, Cr and Mn in a total amount of from 0.005 to 2.0% by mass.
4. The copper alloy strip according to claim 2 , wherein the copper alloy strip further contains one or more of Sn, Zn, Mg, Cr and Mn in a total amount of from 0.005 to 2.0% by mass.
5. The copper alloy strip according to claim 1 , wherein the copper alloy strip has a 0.2% yield strength of 650 MPa to 980 MPa and a conductivity of 34% IACS to 78% IACS.
6. The copper alloy strip according to claim 2 , wherein the copper alloy strip has a 0.2% yield strength of 650 MPa to 980 MPa and a conductivity of 34% IACS to 78% IACS.
7. The copper alloy strip according to claim 1 , wherein the copper alloy has a pressing property of 1<L/L 0 ≤1.15, in which L 0 is a width of the observed surface and L is the total length of a boundary between the sheared surface and the fractured surface.
8. The copper alloy strip according to claim 2 , wherein the copper alloy has a pressing property of 1<L/L 0 ≤1.15, in which L 0 is a width of the observed surface and L is the total length of a boundary between the sheared surface and the fractured surface.
9. The copper alloy strip according to claim 5 , wherein the copper alloy has a pressing property of 1<L/L 0 ≤1.15, in which L 0 is a width of the observed surface and L is the total length of a boundary between the sheared surface and the fractured surface.