Soft magnetic metal strip for electromechanical components

1. A soft-magnetic metal strip, comprising:

a nanocrystalline or amorphous structure, and

a ratio of strip thickness to roughness d/Ra of 5≦d/Ra≦25;

wherein the metal strip has a fish scale pattern with a structure oriented perpendicular and oblique with respect to the longitudinal direction of the strip.

2. The soft magnetic metal strip according to claim 1 , wherein d/Ra is 10≦d/Ra≦20.

3. The soft magnetic metal strip according to claim 1 , wherein the metal strip comprises alloying components of silicon, boron, niobium and copper in more than 73% by atomic weight of iron.

4. The soft magnetic metal strip according to claim 3 , wherein the metal strip comprises an alloy having formula Fe 75.5 Cu 1 Nb 3 Si 12.5 B 8 .

5. The soft magnetic metal strip according to claim 3 , wherein the metal strip comprises an alloy with Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 .

6. The soft magnetic metal strip according to claim 1 , wherein the strip thickness d is 5 μm<d<30 μm.

7. The soft magnetic metal strip according to claim 6 , wherein the strip thickness d is 5 μm<d≦20 μm.

8. The soft magnetic metal strip according to claim 6 , wherein the roughness Ra is 0.6 μm<Ra<2.5 μm.

9. The soft magnetic metal strip according to claim 8 , wherein the roughness Ra is 1 μm<Ra<2 μm.

10. The soft magnetic metal strip according to claim 1 , wherein Br/Bm>80%.

11. The soft magnetic metal strip according to claim 1 , wherein a surface of the metal strip has a surface topology corresponding to a surface structuring of a casting roller.

12. A magnetic core, comprising a wound soft-magnetic metal strip according to claim 1 .

13. An earth leakage circuit breaker having an earth leakage limit value I max ≦30 mA, and comprising a soft magnetic metal strip according to claim 1 .

14. A speed sensor, comprising a soft magnetic metal strip according to claim 1 , in co-operation with a segmented permanent magnet disc.

15. An AC-sensitive electromechanical component comprising a soft-magnetic toroidal strip-wound core comprising a soft magnetic metal strip according to claim 1 .

16. A alternating current ground fault current interrupter circuit comprising the magnetic core according to claim 12 .

17. The alternating current ground fault current interrupter according to claim 16 , wherein, at a current frequency of less than 1000 Hz, the magnetic core has a Br/Bm ratio of greater than 80%.

18. A distribution transformer comprising the magnetic core according to claim 12 .

19. The distribution transformer according to claim 18 , wherein the soft magnetic metal strip is amorphous.