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CN-122000189-A - Method for preparing samarium cobalt permanent magnet material based on pre-ageing treatment

CN122000189ACN 122000189 ACN122000189 ACN 122000189ACN-122000189-A

Abstract

The invention provides a method for preparing a samarium cobalt permanent magnet material based on pre-ageing treatment, and relates to the technical field of samarium cobalt permanent magnet materials. The invention discloses a method for preparing a samarium cobalt permanent magnet material based on pre-ageing treatment, which comprises the steps of precursor preparation, solution treatment, pre-ageing treatment, rapid cooling, main ageing treatment and the like. According to the preparation method, the pre-ageing treatment is adopted, the solute atoms are promoted to be biased to gather at a low temperature to form high-concentration point defects, uniform high-density nucleation sites are provided for the cell wall phase precipitation of the main ageing Sm (Co, cu) 5 , the precipitation kinetics is accelerated, the nano cellular structure is thinned, the microstructure fine regulation is realized, the intrinsic coercivity of the magnet is obviously improved, the residual magnetism and the maximum magnetic energy product of the magnet are cooperatively improved, the cell wall density of the prepared samarium-cobalt permanent magnet material is higher, the distribution is more uniform, and the comprehensive magnetic performance is more excellent.

Inventors

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

Assignees

  • 青海理工学院

Dates

Publication Date
20260508
Application Date
20260316

Claims (10)

  1. 1. The method for preparing the samarium cobalt permanent magnet material based on the pre-ageing treatment is characterized by comprising the following steps of: s1, preparing a precursor, namely crushing a 2:17 type Sm-Co-Fe-Cu-Zr alloy cast ingot, grinding by air flow, orienting by a magnetic field, and sintering in a protective atmosphere to obtain a sintered blank; s2, solution treatment, namely, after the sintered blank is insulated, rapidly cooling to room temperature to obtain supersaturated solid solution; S3, carrying out pre-aging treatment, namely preserving the temperature of the solid solution treated sample within the temperature range of 500-800 ℃ for 3 min-300 min; s4, rapidly cooling, namely immediately cooling the sample to room temperature after the pre-ageing treatment is finished; S5, carrying out primary heat preservation on the sample of the S4, then cooling and carrying out secondary heat preservation, and then air-cooling to room temperature.
  2. 2. The method for preparing the samarium cobalt permanent magnet material based on the pre-aging treatment according to claim 1, wherein the alloy composition of the step S1 comprises, by weight, 23-27% of Sm, 10-20% of Fe, 5-8% of Cu, 1-3% of Zr and the balance Co.
  3. 3. The method for preparing samarium cobalt permanent magnet material based on pre-aging treatment according to claim 1, wherein the average particle size of the powder after air-flow milling in step S1 is 2-6 μm.
  4. 4. The method of claim 1, wherein the step S1 magnetic field orientation is performed in a magnetic field of 1.0 to 2.0T.
  5. 5. The method for preparing the samarium cobalt permanent magnet material based on the pre-aging treatment according to claim 1, wherein the pressure of the compression molding in the step S1 is 150-250 MPa.
  6. 6. The method for preparing the samarium cobalt permanent magnet material based on the pre-aging treatment according to claim 1, wherein in the step S1, the protective atmosphere is argon, hydrogen, nitrogen, argon-hydrogen mixed gas or vacuum, and the vacuum degree is less than or equal to 10 -2 Pa.
  7. 7. The method according to claim 1, wherein in the step S1, the sintering temperature is 1200 ℃ to 1220 ℃ and the sintering time is 1 to 4 h.
  8. 8. The method for preparing the samarium cobalt permanent magnet material based on the pre-aging treatment according to claim 1, wherein in the step S2, the temperature of heat preservation is 1160-1200 ℃, the time of heat preservation is 1-3 h, and the cooling mode is water cooling, air cooling or ice-water mixture quenching.
  9. 9. The method for preparing samarium cobalt permanent magnet material based on pre-aging treatment according to claim 1, wherein the rapid cooling in step S4 is performed by quenching with an ice-water mixture, oil cooling or air cooling.
  10. 10. The samarium cobalt permanent magnet material prepared by the method according to any one of claims 1 to 9, characterized in that the samarium cobalt permanent magnet material has a nano cellular structure, and the structure is composed of Sm 2 (Co,Fe) 17 cellular phase, sm (Co, cu) 5 cell wall phase and Zr-rich lamellar phase.

Description

Method for preparing samarium cobalt permanent magnet material based on pre-ageing treatment Technical Field The invention relates to the technical field of samarium cobalt permanent magnet materials, in particular to a method for preparing a samarium cobalt permanent magnet material based on pre-ageing treatment. Background In rare earth-cobalt intermetallic compounds, sm 2Co17 has higher Curie temperature and saturation magnetization intensity than RCo 5, has higher Curie temperature, excellent temperature stability and corrosion resistance, and is the permanent magnet material with strongest magnetism at high temperature. The high performance of Sm 2Co17 type permanent magnets is derived from its unique nano cellular structure consisting of Sm 2(Co,Fe)17 cell phase, sm (Co, cu) 5 cell wall phase and Zr-rich lamellar phase. The formation of this ideal structure relies on precisely controlled aging heat treatment performed after solution treatment when the material is in a supersaturated solid solution state. The aging process is essentially a process in which solute atoms (Fe, cu, zr) undergo phase separation and precipitation by diffusion, the kinetics and final tissue morphology of which directly determine the overall performance of the magnet. The traditional standard heat treatment process is that after solution treatment, high-temperature long-time main aging is directly carried out, then slow cooling and heat preservation are carried out, and finally air cooling is carried out to room temperature. The process has long period and high energy consumption, and the regulation and control of the microstructure mainly depend on the temperature and time of the main aging stage, and the means are single. The traditional aging process directly carries out high-temperature and long-time main aging on the magnet subjected to solution treatment, has limited control on microstructure, and particularly on alloy rich in Fe, has difficulty in obtaining high coercivity and high squareness while keeping high remanence, so that theoretical magnetic energy product cannot be fully exerted. For magnets with fluctuating components (especially Fe and Cu content) or pursuing higher performance (such as the synergy of high coercivity and high magnetic energy product), the traditional process has a narrow adjustment window, and fine optimization of a microstructure is difficult to realize, so that unstable magnetic performance is easily caused or the potential of materials cannot be fully exerted. Therefore, it is necessary to develop a new heat treatment process, which can realize the cooperative promotion of high coercivity and high squareness while maintaining high remanence, and fine control the microstructure so as to fully exert the magnetic energy product potential of the samarium cobalt permanent magnet material and improve the stability and adaptability of the process. Disclosure of Invention In view of the above, the invention provides a method for preparing samarium cobalt permanent magnet material based on pre-aging treatment, which is characterized in that the defect state before precipitation is systematically regulated and controlled by carrying out the pre-aging and rapid quenching process before main aging treatment, so that the final nano cellular structure is refined, the cooperative promotion of the magnetic performance of the material is realized, the process efficiency and stability are improved, and the problems that the microstructure control is limited and the high-performance cooperative optimization is difficult to realize in the traditional process are solved. The first aspect of the invention provides a method for preparing a samarium cobalt permanent magnet material based on pre-ageing treatment, which comprises the following steps: S1, preparing a precursor, namely smelting a 2:17 type Sm-Co-Fe-Cu-Zr alloy in a vacuum induction smelting furnace, crushing an ingot, grinding by airflow, orienting by a magnetic field, and sintering in a protective atmosphere to obtain a sintered blank; s2, solution treatment, namely, after the sintered blank is insulated, rapidly cooling to room temperature to obtain supersaturated solid solution; S3, carrying out pre-aging treatment, namely preserving the temperature of the solid solution treated sample within the temperature range of 500-800 ℃ for 3 min-300 min; s4, rapidly cooling, namely immediately cooling the sample to room temperature after the pre-ageing treatment is finished; S5, carrying out primary heat preservation on the sample of the S4, then cooling and carrying out secondary heat preservation, and then air-cooling to room temperature. Preferably, the alloy in the step S1 comprises, by weight, 23-27% of Sm, 10-20% of Fe, 5-8% of Cu, 1-3% of Zr and the balance of Co, wherein the average particle size of the powder after air-flow grinding is 2-6 mu m, the orientation of the magnetic field is carried out in a magnetic field of 1.0-2.0T, the pressure of