Copper alloy for electronic and electrical equipment, plastically worked copper alloy material for electronic and electrical equipment, and component and terminal for electronic and electrical equipment

1. A copper alloy for electronic and electrical devices, comprising:

Mg in a range of 1.3 mass % to 2.8 mass %; and

a remainder substantially being Cu and inevitable impurities,

wherein a content of H is set to 10 mass ppm or lower, a content of O is set to 100 mass ppm or lower, a content of S is set to 50 mass ppm or lower, and a content of C is set to 10 mass ppm or lower, and

wherein, R{220} is 0.9 or lower, where an X-ray diffraction intensity from a {111} plane on a plate surface is represented by I{111}, an X-ray diffraction intensity from a {200} plane on the plate surface is represented by I{200}, an X-ray diffraction intensity from a {220} plane on the plate surface is represented by I{220}, an X-ray diffraction intensity from a {311} plane on the plate surface is represented by I{311}, and a fraction {220} of the X-ray diffraction intensity from the {220} plane on the plate surface is R{220}=I{220}/(I{111}+I{200}+I{220}+I{311}).

2. The copper alloy for electronic and electrical devices according to claim 1 ,

wherein, in a scanning electron microscopic observation, an average number of intermetallic compounds which have a particle diameter of 0.1 μm or larger and include Cu and Mg as major components is set to 1 compound/μm 2 or less.

3. The copper alloy for electronic and electrical devices according to claim 1 ,

wherein, in a case where a content of Mg is defined as A atomic %, a conductivity σ (% IACS) is set in a range of σ≤1.7241/(−0.0347×A 2 +0.6569×A+1.7)×100.

4. The copper alloy for electronic and electrical devices according to claim 1 , comprising:

one or more of Sn, Zn, Al, Ni, Si, Mn, Li, Ti, Fe, Co, Cr, Zr, and P in a range of 0.01 mass % to 3.0 mass % in total.

5. The copper alloy for electronic and electrical devices according to claim 1 ,

wherein the copper alloy for electronic and electrical devices has mechanical properties such that a 0.2% yield strength is 400 MPa or higher.

6. The copper alloy for electronic and electrical devices according to claim 1 ,

wherein R{220} is set in a range of 0.3 to 0.9.

7. The copper alloy for electronic and electrical devices according to claim 1 ,

wherein a yield ratio YS/TS, which is calculated from a strength TS and a 0.2% yield strength YS obtained in a tensile test carried out in a direction parallel to a rolling direction, exceeds 90%.

8. The copper alloy for electronic and electrical devices according to claim 7 ,

wherein an average crystal grain size is set to 50 μm or smaller.

9. A plastically-worked copper alloy material for electronic and electrical devices formed by plastically working a copper material made of the copper alloy for electronic and electrical devices according to claim 1 .

10. The plastically-worked copper alloy material for electronic and electrical devices according to claim 9 , wherein the copper alloy material is metal-formed by a manufacturing method including a heat treatment step of heating a copper material to a temperature in a range of 400° C. to 900° C. and cooling the heated copper material to 200° C. or lower at a cooling rate of 60° C./min or greater and a plastic working step of plastically working the copper material.

11. The plastically-worked copper alloy material for electronic and electrical devices according to claim 9 ,

wherein Sn plating is carried out on a surface of the plastically-worked copper alloy material for electronic and electrical devices.

12. A component for electronic and electrical devices made of the plastically-worked copper alloy material for electronic and electrical devices according to claim 9 .

13. A terminal made of the plastically-worked copper alloy material for electronic and electrical devices according to claim 9 .