Method for preparing rare-earth iron series biphase nanocrystalline composite permanent-magnet material

Abstract

The invention belongs to the field of magnetic material. At present much of the permanent magnet material is thin belt or powder, and since the custom sintering process for preparing block material will make the crystal grow, the magnetic property drops significantly. The steps of said invention comprises: the alloy whose component is RxFeyBz, in which R stands for rare-earth Nd or Pr element and the content of x is 4-10, y is 78-88, z is 6-18, is smelted for mother alloy in induction furnace in vacuum; Then preparing the quenched alloy in amorphous, nanometer crystalline state or amorphous-nanometer mixed state by smelting quick-quench method; the linear speed of smelting quick-quench is arranged between 10-50 m / s; under the protection of inertance gas, abrading the alloy into powder whose coarseness is lower than 80 items; encasing the powder into module to precompression and shaping, while range of pressure is 10-1000MPa; carrying the process of discharging plasma sintering, while the sintering temperature is 550Deg C.-700Deg C., the pressure is 30-1000MPa, the elevated temperature speed is 50-500Deg C. / min, the time of heat preservation is 0-10 min, the elevated temperature speed is 50-200Deg C. / min, Said invention can realize high magnetic property material with high degree of compactness, whose crystal grain is smaller than 100 nanometers, and it can be used in high temperature.

Description

1. Technical field [0001] The invention discloses a method for preparing a full-dense bulk rare earth iron-based dual-phase nanocrystalline composite permanent magnet material, which belongs to the technical field of magnetic materials. 2. Background technology [0002] Nanocrystalline composite rare earth permanent magnet materials are a new type of rare earth permanent magnet materials. Its characteristic is that the soft magnetic phase with high saturation magnetization and the permanent magnetic phase with high coercive force are exchange-coupled at nanometer size to form a two-phase composite permanent magnetic material with high remanence and high coercive force. Calculations have shown that such materials have properties as high as 1090kJ / m 3 The theoretical maximum magnetic energy product (Skomski R, Coey JM D. Phys. Rev. B 1994, 48: 15812). At present, people have prepared Nd by means of melt rapid quenching method and mechanical alloying method. 2 Fe 14 B / Fe 3...

AI Technical Summary

Problems solved by technology

However, there is a problem in the practical application of this kind of permanent magnet materials. Specifically, most of the materials currently prepared are thin strips or powders, and the preparation of fully dense bulk materials by traditional sintering processes will result in long material grains. Large, which significantly reduces the magnetic properties, so it can only be made into bonded magnets, which causes a sharp drop in the magnetic properties of the magnets

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