IP Library Granted Patent US 12,424,359
Granted Patent B2
US 12,424,359 · App. 17/630,596 · Granted Sep 23, 2025

R-T-B series permanent magnet material, raw material composition preparation method and application

Inventors: Qin Lan (Fujian, CN); Dawei Shi (Fujian, CN); Jiaying Huang (Fujian, CN)
Assignee: FUJIAN GOLDEN DRAGON RARE-EARTH Co., Ltd.
H01F1/0577B22F9/04C22C38/002C22C38/005C22C38/10C22C38/14C22C38/16B22F2201/03B22F2301/355C22C2202/02Y10T428/12014
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Quick Facts
Patent No.
US 12,424,359
App. No.
17/630,596
Granted
Sep 23, 2025
Kind
B2
Abstract

An R-T-B series permanent magnet material, a raw material composition, a preparation method, and an application. The R-T-B series permanent magnet material comprises the following components: R: 29-31.0 wt. %, RH is greater than 1 wt. %, B: 0.905-0.945 wt. %, C: 0.04-0.15 wt. %, N: 0.1-0.4 wt. %, and Fe: 67-69 wt. %, wherein R comprises RL and RH, RL is a light rare earth element, RL comprises Nd, RH is a heavy rare earth element, a (RL 1-y RH y ) 2 T 17 C x phase is present at the grain boundary of the R-T-B series permanent magnet material, x: 2-3, y: 0.15-0.35, and T must comprise Fe, and also comprises one or more among Co, Ti and N. The permanent magnet material retains relative high Br and Hcj under different heat treatment temperatures.

Claims (44)

1. An R-T-B series permanent magnet material, comprising, by mass percentage, the following components:

29-31.0 wt. % of R,

greater than 1 wt. % of RH,

0.905-0.945 wt. % of B,

0.04-0.15 wt. % of C,

0.1-0.4 wt. % of Q,

67-69 wt. % of Fe,

wherein wt. % refers to the mass percentage relative to the R-T-B series permanent magnet material;

the R-T-B series permanent magnet material further comprises Co and Ti;

Q includes Cu and/or Ga;

R includes RL and RH, wherein RL is a light rare earth element, including Nd, and RH is a heavy rare earth element;

an (RL 1-y RH y ) 2 T 17 C x phase is present at the grain boundary of the R-T-B series permanent magnet material, wherein x is 2-3, y is 0.15-0.35, and T necessarily includes Fe, and also includes one or more of Co, Ti and Q;

wherein the range of the content of Ti is 0.05-0.2 wt. % or 0.1-0.25 wt. %.

2. The R-T-B series permanent magnet material according to claim 1 , wherein the R-T-B series permanent magnet material further comprises the element M, and the element M includes one or more of Al, Si, Sn, Ge, Ag, Au, Bi, Mn, Cr, Zr, Nb, and Hf.

3. The R-T-B series permanent magnet material according to claim 2 , wherein the range of the content of M is 0-3 wt. %, exclusive of 0 wt. %.

4. The R-T-B series permanent magnet material according to claim 1 , wherein the range of the content of R is 30.2-31.0 wt. % or 29-30.4 wt. %;

or, the range of the content of B is 0.905-0.93 wt. % or 0.915-0.945 wt. %.

5. The R-T-B series permanent magnet material according to claim 1 , wherein, when Q includes Cu, the range of the content of Cu is 0.05-0.20 wt. %;

or, when Q includes Ga, the range of the content of Ga is 0.05-0.20 wt. %.

6. The R-T-B series permanent magnet material according to claim 1 , wherein the R-T-B series permanent magnet material further comprises O, the range of the content of O is 0.08-0.12 wt. %.

7. The R-T-B series permanent magnet material according to claim 1 , wherein the type of RH includes Dy and/or Tb.

8. The R-T-B series permanent magnet material according to claim 1 , wherein the range of the content of RH is 1-2.5 wt. %, exclusive of 1 wt. %.

9. The R-T-B series permanent magnet material according to claim 1 , wherein the range of the content of C is 0.1-0.15 wt. % or 0.04-0.12 wt. %.

10. A raw material composition for an R-T-B series permanent magnet material, comprising, by mass percentage, the following components:

28.5-30.5 wt. % of R,

0.905-0.945 wt. % of B,

0.1-0.4 wt. % of Q,

67-69 wt. % of Fe,

wherein the raw material composition for the R-T-B series permanent magnet material comprises Ti and Co;

wt. % refers to the mass percentage relative to the raw material composition for the R-T-B series permanent magnet material;

Q includes Cu and/or Ga;

R includes RL and RH, wherein RL is a light rare earth element, including Nd, and RH is a heavy rare earth element;

an (RL 1-y RH y ) 2 T 17 C x phase is present at the grain boundary of the R-T-B series permanent magnet material, wherein x is 2-3, y is 0.15-0.35, and T necessarily includes Fe, and also includes one or more of Co, Ti and Q;

wherein, the range of the content of Ti is 0.05-0.2 wt. % or 0.1-0.25 wt. %.

11. The raw material composition for the R-T-B series permanent magnet material according to claim 10 , wherein the raw material composition for the R-T-B series permanent magnet material further comprises the element M, and the element M includes one or more of Al, Si, Sn, Ge, Ag, Au, Bi, Mn, Cr, Zr, Nb, and Hf.

12. A method for preparing an R-T-B series permanent magnet material, comprising the following step: subjecting a melt of the raw material composition for the R-T-B series permanent magnet material according to claim 10 to casting, crushing, pulverization, forming, sintering, a grain boundary diffusion treatment, and a heat treatment.

13. The preparation method according to claim 12 , wherein the pulverization process is carried out in an atmosphere with an oxidizing gas content of 100 ppm or less;

or, after pulverization, a lubricant is added, in an amount of 0.05-0.15%, relative to the weight of the pulverized powder;

or, the heat treatment temperature is 470-510° C., 460-500° C., or 480-520° C.

14. An R-T-B series permanent magnet material prepared by the preparation method according to claim 12 .

15. The raw material composition for the R-T-B series permanent magnet material according to claim 10 , wherein, when Q includes Cu, the range of the content of Cu is 0.05-0.20 wt. %;

or, when Q includes Ga, the range of the content of Ga is 0.05-0.20 wt. %.

16. The raw material composition for the R-T-B series permanent magnet material according to claim 10 , wherein, the type of RH includes Dy and/or Tb;

or, the range of the content of RH is 0.5-2 wt. %, exclusive of 0.5 wt. %.

Assignments (3)
CHANGE OF NAME Recorded Jan 4, 2024
From: FUJIAN CHANGTING GOLDEN DRAGON RARE-EARTH CO., LTD
To: FUJIAN GOLDEN DRAGON RARE-EARTH CO., LTD.
Reel/Frame 066188/0731 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 20, 2022
From: XIAMEN TUNGSTEN CO., LTD.
To: FUJIAN CHANGTING GOLDEN DRAGON RARE-EARTH CO., LTD
Reel/Frame 060533/0452 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 27, 2022
From: LAN, QIN; SHI, DAWEI; HUANG, JIAYING
To: XIAMEN TUNGSTEN CO., LTD.; FUJIAN CHANGTING GOLDEN DRAGON RARE-EARTH CO., LTD
Reel/Frame 058800/0542 →
Priority Claims (1)
CN 201911418433.8 · Dec 31, 2019 · national
Continuity (1)
Related Publication 20220344083A1 · Oct 27, 2022
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