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CN-122025323-A - Joule heating aging treatment method for samarium cobalt-based rare earth permanent magnet material

CN122025323ACN 122025323 ACN122025323 ACN 122025323ACN-122025323-A

Abstract

The invention provides a joule heating aging treatment method for a samarium cobalt-based rare earth permanent magnet material, and relates to the technical field of rare earth permanent magnet materials. The invention relates to a joule heating aging treatment method of a samarium cobalt-based rare earth permanent magnet material, which comprises ingot casting preparation, crushing and pulverizing, forming and solution treatment, joule heating aging treatment and cooling treatment. The invention adopts Joule heating strong pulse current to rapidly process samarium cobalt permanent magnet material, inhibits atom migration agglomeration, retains high-density vacancy defects and dislocation, promotes cell wall phase nucleation, greatly shortens heat preservation time, and improves efficiency by several times. The material prepared by the invention has uniform and fine nano cellular tissue, the key magnetic property reaches the commercial level and is even better, the process is simple, and the material is suitable for industrial production and has good application prospect.

Inventors

  • ZHU SHENGZHI
  • Chu Baikun
  • MA GUOJUAN
  • XU LINQIAN

Assignees

  • 青海理工学院

Dates

Publication Date
20260512
Application Date
20260319

Claims (9)

  1. 1. A joule heating aging treatment method for samarium cobalt-based rare earth permanent magnet material is characterized by comprising the following steps: s1, preparing an ingot, namely preparing a samarium cobalt alloy ingot by adopting a powder metallurgy process; s2, crushing and pulverizing, namely crushing the cast ingot and preparing the crushed cast ingot into powder; s3, forming and solution treatment, namely performing magnetic field orientation forming and pressing on the powder, and then performing sintering and solution treatment to obtain a solid solution state magnet; S4, performing joule heating aging treatment, namely heating the solid solution state magnet to 810-890 ℃ in 20-45 min by adopting a joule heating method, and preserving heat for 5 min-5 h to complete the aging treatment; S5, cooling treatment, namely cooling to room temperature after ageing treatment; Or cooling to 380-420 ℃ at a cooling rate of 10-20 ℃ per minute, performing secondary aging, and cooling to room temperature; or cooling to 380-420 deg.C at a cooling rate of 10-20 deg.C/min, and directly cooling to room temperature.
  2. 2. The method for joule heating aging treatment of samarium cobalt-based rare earth permanent magnet material according to claim 1, wherein in the step S1, a powder metallurgy process is adopted to prepare a samarium cobalt alloy ingot containing Sm, co, fe, cu and Zr alloy elements.
  3. 3. The method for joule heating aging treatment of samarium cobalt based rare earth permanent magnet material according to claim 1, wherein in the step S2, the cast ingot is ground into powder of 2-6 μm by an air flow mill or a ball mill method.
  4. 4. The method according to claim 1, wherein in the step S4, the joule heating is performed by using graphite as a reactor and a short-time strong pulse current.
  5. 5. The method for joule heating aging treatment of samarium cobalt-based rare earth permanent magnet material according to claim 1, wherein in the step S4, the heating rate is 20-40 ℃ per minute, the aging temperature is 830-860 ℃ and the heat preservation time is 0.5-3 h.
  6. 6. The method for joule heating aging treatment of samarium cobalt-based rare earth permanent magnet material according to claim 1, wherein in the step S5, the temperature of the secondary aging is 380 ℃, and the heat preservation time of the secondary aging is 0.5-1 h.
  7. 7. The method for joule heating aging treatment of samarium cobalt-based rare earth permanent magnet material according to claim 1, wherein in the step S5, the cooling rate is 6-20 ℃.
  8. 8. The method for joule heating aging treatment of samarium cobalt based rare earth permanent magnet material according to claim 1, wherein the overall aging time is 80-285 min.
  9. 9. The samarium cobalt-based rare earth permanent magnet material prepared by the method of any one of claims 1 to 8, which is characterized by having a uniform and complete nano cellular tissue structure, and comprising a intracellular phase, a Fe-rich Sm 2 Co 17 R rhombus phase, a cell wall phase, a Cu-rich SmCo 5 H hexagonal phase and a lamellar phase, wherein the lamellar phase is a Zr-rich SmCo 3 R lamellar phase, and penetrates through the cellular tissue.

Description

Joule heating aging treatment method for samarium cobalt-based rare earth permanent magnet material Technical Field The invention relates to the technical field of rare earth permanent magnet materials, in particular to a joule heating aging treatment method of a samarium cobalt-based rare earth permanent magnet material. Background The samarium cobalt rare earth permanent magnet material has higher Curie temperature, excellent temperature stability and corrosion resistance, is the permanent magnet material with strongest magnetism in a high-temperature environment, and has wide application prospect in the high-end fields of aerospace, microwave communication and the like. The samarium cobalt permanent magnet material is generally prepared by adopting a powder metallurgy process, and the process flow comprises a plurality of links such as smelting, crushing, powder preparation, magnetic field orientation molding, pressing, heat treatment and the like. Wherein, the heat treatment process comprises the key steps of sintering, solid solution, aging and the like, and plays a decisive role in the final magnetic property of the material. However, the conventional aging process adopts a conventional heating mode such as a box furnace or a tube furnace, and the like, and has the problems of slow heating rate and long treatment time. The slow heating process causes annihilation of dislocation in the solid solution state alloy in the heating stage, sacrifices a defect structure in the material, weakens the driving force of nucleation of a precipitated phase in the subsequent phase decomposition process, and therefore, the driving force must be compensated by prolonging the heat preservation time, which not only causes overlong heat treatment period and low production efficiency, but also brings a series of problems of high energy consumption, increased production cost and the like, and severely restricts the industrialized production efficiency of the samarium cobalt rare earth permanent magnet material. In addition, the long-time high-temperature heat preservation also easily causes the growth and coarsening of cellular tissues, and the magnetic property of the material is adversely affected. Therefore, development of a novel aging treatment method capable of shortening aging treatment time, improving production efficiency and reducing energy consumption and ensuring that the samarium cobalt-based rare earth permanent magnet material obtains excellent magnetic performance and an ideal microstructure is urgently needed. Disclosure of Invention In view of the above, the invention provides a joule heating aging treatment method for samarium cobalt-based rare earth permanent magnet materials, which adopts a joule heating technology to realize rapid temperature rise, effectively retains a high-density defect structure inside the materials, and promotes nucleation in a phase decomposition process, so that uniform and complete nano cellular tissues and excellent comprehensive magnetic properties are obtained while the aging time is greatly shortened. The first aspect of the invention provides a joule heating aging treatment method of a samarium cobalt-based rare earth permanent magnet material, which comprises the following steps: s1, preparing an ingot, namely preparing a samarium cobalt alloy ingot by adopting a powder metallurgy process; s2, crushing and pulverizing, namely crushing the cast ingot and preparing the crushed cast ingot into powder; s3, forming and solution treatment, namely performing magnetic field orientation forming and pressing on the powder, and then performing sintering and solution treatment to obtain a solid solution state magnet; S4, performing joule heating aging treatment, namely heating the solid solution state magnet to 810-890 ℃ in 20-45 min by adopting a joule heating method, and preserving heat for 5 min-5 h to complete the aging treatment; S5, cooling treatment, namely cooling to room temperature after ageing treatment; Or cooling to 380-420 ℃ at a cooling rate of 10-20 ℃ per minute, performing secondary aging, and cooling to room temperature; or cooling to 380-420 deg.C at a cooling rate of 10-20 deg.C/min, and directly cooling to room temperature. Preferably, in the step S1, a powder metallurgy process is used to prepare a samarium cobalt alloy ingot containing Sm, co, fe, cu and Zr alloy elements. Preferably, in the step S2, the ingot is ground into powder of 2-6 μm by an air flow mill or a ball mill method. Preferably, in the step S4, the joule heating is realized by taking graphite as a reactor and passing a strong pulse current for a short time, the heating rate is 20-40 ℃ per minute, the aging temperature is 830-860 ℃, and the heat preservation time is 0.5-3 h. Preferably, in the step S5, the temperature of the secondary aging is 380 ℃, and the heat preservation time of the secondary aging is 0.5-1 h. More preferably, in the step S5, the cooling rate is 6-20 ℃ per min. Preferably,