Low loss magnetodielectric material

Patent metadata

Field	Value
Publication number	US-12381025-B2
Application number	US-202217741746-A
Country	US
Kind code	B2
Filing date	May 11, 2022
Priority date	May 17, 2021
Publication date	Aug 5, 2025
Grant date	Aug 5, 2025

Abstract

In an aspect, a Co 2 Z-type ferrite comprises oxides of at least Me, Co, Mo, Li, and Fe; wherein Me is at least one of Ba or Sr. In another aspect, the Co 2 Z-type ferrite comprises a Z-type hexaferrite an amount of lithium molybdate. In another aspect, the Co 2 Z-type ferrite has a formula Li 2 MoO 4 ·Ba x Sr 3-x Co 2+y−z Me′ y Me″ z Fe 24-2y-m O 41 , wherein Me′ is at least one of Ti, Mo, Ru, Ir, Zr, or Sn; Me″ is at least one of Zn, Mn, or Mg; x is 0 to 3; y is 0 to 1.8; z is 0 to 1.8; and m is −4 to 4. In yet another aspect, a method of making a Co 2 Z-type ferrite comprises milling an initial Co 2 Z-type ferrite and Li 2 MoO 4 to form a mixed ferrite; and calcining the mixed ferrite to form the Co 2 Z-type ferrite.

First claim

What is claimed is:

1. A Co 2 Z-type ferrite, comprising:
oxides of at least Me, Co, Mo, Li, and Fe;
wherein Me is at least one of Ba or Sr.

2. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite has a formula Li 2 MoO 4 ·Ba x Sr 3-x Co 2+y-z Me′ y Me″ z Fe 24-2y-m O 41 , wherein Me′ is at least one of Ti, Mo, Ru, Ir, Zr, or Sn; Me″ is at least one of Zn, Mn, or Mg; x is 0 to 3; y is 0 to 1.8; z is 0 to 1.8; and m is −4 to 4.

3. The Co 2 Z-type ferrite of claim 2 , wherein at least one of
x is 0.1 to 3;
y is 0 to 1.5;
z is 0 to 1.5; or
m is −3 to 4.

4. The Co 2 Z-type ferrite of claim 2 , wherein the Co 2 Z-type ferrite has the formula of Li 2 MoO 4 ·Ba x Sr 3-x Co 2 Fe 24-m O 41 ; wherein x is 0 to 3; wherein m is −4 to 4.

5. The Co 2 Z-type ferrite of claim 2 , wherein the Li 2 MoO 4 is present in an amount of 0.1 to 1 weight percent based on a total weight of the Co 2 Z-type ferrite.

6. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite comprises
a magnetic phase having the formula Ba x Sr 3-x CO 2+y-z Me y Me′ z Fe 24-2y-m O 41 , wherein Me′ is at least one of Ti, Mo, Ru, Ir, Zr, or Sn; Me′ is at least one of Zn, Mn, or Mg; x is 0 to 3; y is 0 to 1.8; z is 0 to 1.8; and m is −4 to 4; and
a dielectric phase having the formula Li 2 MoO 4 .

7. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite has a D 50 particle size of 2 to 10 micrometers; or wherein the Co 2 Z-type ferrite has a porosity of 0 to 50 volume percent based on the total volume of the Co 2 Z-type ferrite.

8. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite has a permeability of greater than or equal to 2 at a frequency of 0.5 to 2 gigahertz; or wherein the Co 2 Z-type ferrite has a magnetic loss tangent tan δ μ of less than or equal to 0.3 at a frequency of 0.5 to 2 gigahertz.

9. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite has a permittivity of less than or equal to 8 at a frequency of 0.5 to 2 gigahertz.

10. The Co 2 Z-type ferrite of claim 1 , wherein the Co 2 Z-type ferrite has a dielectric loss tangent tan δ ε of less than or equal to 0.01 at a frequency of 0.5 to 2 gigahertz.

11. A composite comprising a polymer and the Co 2 Z-type ferrite of claim 1 .

12. The composite of claim 11 , wherein the polymer comprises at least one of a fluoropolymer, a polyurethane, a silicone polymer, a liquid crystalline polymer, a polyketone, a polysulfone, or a polyolefin.

13. An article comprising the ferrite composition of claim 1 .

14. The article of claim 13 , wherein the article is an antenna, a filter, an inductor, a circulator, or an EMI suppressor.

15. A method of making the Co 2 Z-type ferrite of claim 1 comprising:
milling an initial Co 2 Z-type ferrite and LiMoO 4 to form a mixed ferrite; and
calcining the mixed ferrite to form the Co 2 Z-type ferrite.

16. The method of claim 15 , wherein the milling occurs for greater than or equal to 1.5 hours; or at a mixing speed of greater than or equal to 300 revolutions per minute.

17. The method of claim 15 , further comprising:
milling ferrite precursor compounds comprising oxides of Me, Co, Me′, Me″, and Fe, to form a magnetic oxide mixture; wherein Me comprises at least one of Ba or Sr; Me′ is at least one of Ti, Mo, Ru, Ir, Zr, or Sn; and Me″ is at least one of Zn, Mn, or Mg;
calcining the magnetic oxide mixture in an oxygen or air atmosphere to form the initial Co 2 Z-type ferrite having the formula Ba x Sr 3-x CO 2+y-z Me′ y Me″ z Fe 24-2y-m O 41 , wherein Me′ is at least one of Ti, Mo, Ru, Ir, Zr, or Sn; Me″ is at least one of Zn, Mn, or Mg; x is 0 to 3; y is 0 to 1.8; z is 0 to 1.8; and m is −4 to 4.

18. The method of claim 15 , further comprising milling Li 2 CO 3 and MoO 2 to form a dielectric oxide mixture; and calcining the dielectric oxide mixture in an oxygen or air atmosphere to form the Li 2 MoO 4 .

19. The method of claim 15 , wherein the calcining the mixed ferrite occurs at a calcining temperature of 800 to 1,300° C. or for a calcining time of 0.5 to 20 hours.

20. The method of claim 15 , further comprising forming a composite comprising the Co 2 Z-type ferrite and a polymer.

Assignees

• Rogers Corp

Inventors

• Chen Yajie
• Young Lance
• Li Qifan
• Hott Megan

Classifications

• C08K2201/01

  Magnetic additives · CPC title

• C08K2003/2289

  of cobalt · CPC title

• C08K3/22

  of metals · CPC title

• C04B2235/6583

  Oxygen containing atmosphere, e.g. with changing oxygen pressures · CPC title

• C04B2235/6567

  Treatment time · CPC title