Composite hexagonal ferrite materials
Disclosed herein are embodiments of composite hexagonal ferrite materials formed from a combination of Y phase and Z phase hexagonal ferrite materials. Advantageously, embodiments of the material can have a high resonant frequency as well as a high permeability. In some embodiments, the materials can be useful for magnetodielectric antennas.
1. A method of forming a composite hexagonal ferrite material, the method comprising combining a base y-phase hexagonal ferrite composition having a formula Sr 2−2x Na 2x Zr x Co 2−x Fe 12 O 22 or Sr 2−x Na x In x Co 2−x Fe 12 O 22 , 0<x<1 at least partially with a doped-in z-phase hexagonal ferrite composition having a formula Sr 3-x′-y′ Ba x′ Na y′ Co 2−y′ In y′ Fe 24 O 41 , 0<x′<3 and 0<y′<1.
2. The method of claim 1 further comprising forming an antenna from the composite hexagonal ferrite material.
3. A method of forming a composite hexagonal ferrite material, the method comprising combining a base y-phase hexagonal ferrite composition, the base y-phase hexagonal ferrite composition having a formula Sr 2−x′ Na x′ In x′ Co 2−x′ Fe 12 O 22 , 0<x′<1 at least partially with a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material, the doped-in z-phase hexagonal ferrite composition having a formula Sr 3-x-2y Ba x Na 2y Co 2−y Zr y Fe 24 O 41 , or Sr 3-x-y Ba x Na y Co 2−y In y Fe 24 O 41 , 0<x<3, and 0<y<1.
4. The method of claim 3 further comprising forming an antenna from the composite hexagonal ferrite material.
5. A method of forming a composite hexagonal ferrite material, the method comprising combining a base y-phase hexagonal ferrite composition having a formula Sr 2−x′ Na x′ Co 2−x′ Sc x′ Fe 12 O 22 , 0<x′<1 at least partially with a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material, the doped-in z-phase hexagonal ferrite composition having a formula Sr 3-x-y Ba x Na y Co 2−y Sc y Fe 24 O 41 , 0<x<3, 0<y<1.5.
6. The method of claim 5 wherein the composite hexagonal ferrite material includes two phases.
7. The method of claim 5 wherein composite hexagonal ferrite material has a real permeability of between 3 and 7 at 1 GHz.
8. The method of claim 5 wherein the composite hexagonal ferrite material has a real permeability of greater than 6 at 1 GHz.
9. The method of claim 5 wherein the base y-phase hexagonal ferrite composition includes Sr 1.6 Na 0.4 Sc 0.4 Co 1.6 Fe 12 O 22 .
10. The method of claim 5 wherein the doped-in z-phase hexagonal ferrite composition includes Ba 1.4 Sr 0.8 Na 0.8 Sc 0.8 Co 1.2 Fe 12 O 22 .
11. The method of claim 5 further comprising forming an antenna from the composite hexagonal ferrite material.
12. The method of claim 11 wherein the antenna has a bandwidth between 100 MHz and 1 GHz.
13. The method of claim 5 wherein the composite hexagonal ferrite material has a Q value greater than 20 at 1 GHz.
14. The method of claim 5 wherein the composite hexagonal ferrite material has a real permeability above 4.
15. A method of forming a composite hexagonal ferrite material, the method comprising combining a base y-phase hexagonal ferrite composition having a formula Sr 2−x Na x In x Co 2−x Fe 12 O 22 , 0<x<1 at least partially with a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material.
16. The method of claim 15 further comprising forming an antenna from the composite hexagonal ferrite material.
17. A method of forming a composite hexagonal ferrite material, the method comprising combining a base y-phase hexagonal ferrite composition at least partially with a doped-in z-phase hexagonal ferrite composition to form the composite hexagonal ferrite material, the doped-in z-phase hexagonal ferrite composition having a formula Sr 3-x-y Ba x Na y Co 2−y In y Fe 24 O 41 , 0<x<3, and 0<y<1.
18. The method of claim 17 further comprising forming an antenna from the composite hexagonal ferrite material.