Soft magnetic alloy and uses thereof
The invention discloses a soft magnetic amorphous alloy and a soft magnetic nanocomposite alloy formed from the amorphous alloy. Both alloys comprise a composition expressed by the following formula: (Fe 1-x-y Co x M y ) 100-a-b-c T a B b N c where, M is at least one element selected from the group consisting of Ni and Mn; T is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti, Cr, Cu, Mo, V and combinations thereof, and the content of Cu when present is less than or equal to 2 atomic %; N is at least one element selected from the group consisting of Si, Ge, C, P and Al; and 0.01≦x+y≦0.5; 0≦y≦0.4; 1≦a≦5 atomic %; 10≦b≦30 atomic %; and 0≦c≦10 atomic %. A core, which may be used in transformers and wire coils, is made by charging a furnace with elements necessary to form the amorphous alloy, rapidly quenching the alloy, forming a core from the alloy; and heating the core in the presence of a magnetic field to form the nanocomposite alloy. The resulting nanocomposite alloy of the core comprises the amorphous alloy having embedded therein, fine grain nanocrystalline particles, about 90% of which are 20 nm in any dimension.
1. A soft magnetic alloy comprising a composition expressed by the following formula:
(Fe 1-x-y Co x M y ) 100-a-b-c T a B b N c
where, M is at least one element selected from the group consisting of Ni and Mn;
T is at least one element selected from the group consisting of Nb, W, Ta, Zr, Hf, Ti, Cr, Cu, Mo, V and combinations thereof, and the content of Cu when present is less than or equal to 2 atomic %;
N is at least one element selected from the group consisting of Si, Ge, C, P and Al;
0.01 ≦x+y≦ 0.5;
0 ≦y≦ 0.4;
1 ≦a≦ 5 atomic %;
10 ≦b≦ 30 atomic %;
0 ≦c≦ 10 atomic %.
2. The alloy of claim 1 , wherein 0.2≦x≦0.3.
3. The alloy of claim 1 , wherein 0.1≦x≦0.5.
4. The alloy of claim 1 , wherein 0≦y≦0.1.
5. The alloy of claim 1 , wherein y=0.
6. The alloy of claim 1 , wherein 3≦a≦5 atomic %.
7. The alloy of claim 1 , wherein 10≦b≦20 atomic %.
8. The alloy of claim 1 , wherein 2≦c≦5 atomic %.
9. The alloy of claim 1 , wherein T is an element selected from the group consisting of Nb, Cu, Zr and combinations thereof.
10. The alloy of claim 1 , wherein T is two elements selected from the group consisting of Nb, Cu and Zr.
11. The alloy of claim 1 , wherein N is an element selected from the group consisting of Ge and Si and Si, if present, is present in an amount up to 5 atomic %.
12. The alloy of claim 1 , wherein N is Si present in an amount ranging from 2 to 5 atomic %.
13. The alloy of any of claim 1 , wherein N is Ge present in an amount up to 2 atomic %.
14. The alloy of claim 1 , wherein T is Nb present at 4 atomic % and Cu present at one atomic %.
15. The alloy of claim 1 , wherein the ratio of Co to Fe is greater than 0 and less than 0.5.
16. The alloy of claim 1 , wherein the ratio of Co to Fe is greater than 0.2 and less than 0.3.
17. The alloy of claim 1 , wherein Fe and Co together comprise between 75 and 89 atomic %.
18. The alloy recited in claim 1 , wherein Fe and Co together comprise 80 atomic %, y is zero, T is Nb present at 4-5 atomic %, B is present at 13-15 atomic percent and N is selected from the group consisting of Si and Ge and is present at 0-2 atomic %.
19. The alloy recited in claim 16 , wherein B is present at 13 atomic % and N is present at 2 atomic %.
20. The alloy of claim 1 , wherein the content of a group consisting of Fe and Co and at least one of Ni and Mn is between 55 and 89 atomic %.
21. The alloy of claim 1 , wherein the content of a group consisting of Fe and Co and at least one of Ni and Mn is between about 80 atomic %.
22. The alloy of claim 1 , wherein the content of a group consisting of Co in combination with at least one of Ni and Mn is about 8 to 15 atomic %.
23. The soft magnetic alloy of claim 1 , wherein the alloy is a nanocomposite alloy comprising an amorphous phase and a crystalline phase.
24. The nanocomposite alloy of claim 23 , wherein the crystalline phase of the alloy comprises crystalline particles embedded in the amorphous phase, wherein at least 90% of the crystalline particles are less than or equal to 20 nanometers in any dimension and the nanocomposite alloy has a saturation flux density of greater than 1 Tesla (T) and a linear magnetization curve up to between 550 A/m and 700 A/m and the amorphous phase of the alloy has a Curie temperature greater than 450° C.
25. The nanocomposite alloy of claim 23 , wherein the nanocomposite alloy has a saturation flux density of greater than 1 Tesla (T).
26. The nanocomposite alloy of claim 23 , wherein the nanocomposite alloy has a saturation flux density of between 1 T and 2 T.
27. The nanocomposite alloy of claim 23 , wherein the alloy has a saturation flux density of between 1 T and 1.6 T.
28. The nanocomposite alloy of claim 23 , wherein the alloy has a linear magnetization curve up to 700 amps (A)/meter (m).
29. The nanocomposite alloy of claim 23 , wherein the alloy has a linear magnetization curve up to between 550 A/m and 700 A/m.
30. The nanocomposite alloy of claim 23 , wherein the alloy comprises crystalline particles embedded in an amorphous matrix.
31. The nanocomposite alloy of claim 30 , wherein at least 90% of the crystalline particles are less than or equal to 20 nanometers in any dimension.
32. The nanocomposite alloy of claim 23 , wherein the amorphous phase of the alloy has a Curie temperature greater than 450° C.
33. The nanocomposite alloy of claim 23 , wherein the amorphous phase of the alloy has a Curie temperature between 450° C. and 750° C.
34. The nanocomposite alloy of claim 23 , wherein the alloy has a core loss less of between 25 and 80 W/kg at 0.1 T and 100 kHz and a core loss of less than 10 W/kg at 0.2 T and 20 kHz.
35. The nanocomposite alloy of claim 23 , having a squareness ratio of less than 10%.
36. The nanocomposite alloy of claim 23 , having a squareness ratio between about 1 and 6%.
37. A transformer comprising a core manufactured from the soft magnetic nanocomposite alloy recited in claim 23 .
38. The transformer of claim 37 , wherein the transformer is a current transformer.
39. The transformer of claim 38 , wherein the transformer is a power transformer.
40. The transformer of claim 38 , wherein the transformer is a pulse transformer.
41. A wire coil formed around a core manufactured from the soft magnetic nanocomposite alloy recited in claim 23 .
42. The wire coil of claim 41 , wherein the wire coil is part of a transformer.
43. The wire coil of claim 41 , wherein the wire coil is part of an inductor.
44. The wire coil of claim 41 , wherein the wire coil is part of a choke coil.
45. The soft magnetic alloy of claim 1 , wherein the alloy is amorphous.