A kind of preparation method of nanometer magnetic particle

Abstract

The invention discloses a preparation method for nano magnetic particles. The preparation method comprises the following steps: mixing samarium nitrate (Sm(NO3)3) and cobalt nitrate (Co(NO3)3) solution in proportion; then respectively adding copper nitrate (Cu(NO3)2), ferric nitrate (Fe(NO3)3) and zirconium nitrate (Zr(NO3)4), and performing uniform stirring; performing drying, mixing with NaCl, crushing, ball milling, reduction treatment, secondary ball milling and the like to prepare a nano-scale particle material with the general formula of SmCoxFeaCubZrc, wherein in the formula, x, a, b and c represent the atomic contents of Co, Fe, Cu and Zr; x=4.5-5.5, a=0.05-0.1, b=0.05-0.1, c=0.02-0.08. The production equipment of the material is simple, and the production can be completed by utilizing a ball mill, a treatment furnace and crushing equipment for production. The particle size of the material is effectively controlled through the combination of multiple technologies, and the material is guaranteed to have the very high magnetic performance.

Description

technical field [0001] The invention belongs to the technical field of rare earth permanent magnet materials, and in particular relates to a preparation method of nanometer magnetic particles. Background technique [0002] Magnetic material is a basic functional material and an important material basis indispensable to the development of modern science and technology and the world economy. Among them, magnetic nanoparticles, as a special magnetic material, are widely used in the fields of permanent magnet devices, medicine and electronic products. At present, the common nano-strong magnetic particles are generally iron-platinum materials, but due to the high price of metal platinum, this material is expensive, which seriously limits its market application. [0003] Compared with iron-platinum alloys, rare earth permanent magnet materials such as samarium cobalt, neodymium iron boron, samarium iron nitrogen, etc. have stronger magnetic properties, but due to the instability ...

AI Technical Summary

Problems solved by technology

At present, the common nano-strong magnetic particles are generally iron-platinum materials, but due to the high price of metal platinum, this material is expensive, which seriously limits its market application.

[0003] Compared with iron-platinum alloys, rare earth permanent magnet materials such as samarium cobalt, neodymium iron boron, samarium iron nitrogen, etc. have stronger magnetic properties, but due to the instability and easy oxidation of the material, it is difficult to make nanoparticles

Methods for preparing nanocrystalline samarium cobalt or nanocrystalline neodymium iron boron magnetic materials have been published in the current prior art. The microstructure (such as crystal grains) of these materials has indeed reached the nanometer scale, but their macroscopic morphology (such as particles) However, it is still tens to hundreds of microns, which cannot be regarded as magnetic nanoparticles.

For example, the patent application number 201710801608.8 discloses a method for preparing samarium-cobalt compound nanoparticles with adjustable composition and particle size. In the absence of oxygen, Sm was successfully prepared by in situ generation and in situ collection of evaporation and condensation. 2 co 7 、SmCo 5 、SmCo 7 、Sm 2 co 17 A variety of samarium-cobalt compound nanoparticles with an average particle size of less than 100 nanometers and a controllable particle size. Although this method prepares nanoscale magnetic particles, the material cost is relatively high due to the use of elemental samarium and elemental cobalt metal; and , its production methods, such as in-situ generation, in-situ collection, and evaporation and condensation processes, have low production efficiency

The patent application number 200910236640.1 discloses a method for synthesizing magnetic nano-samarium cobalt particles from polyols. The magnetic particles prepared by this method are about 20nm in size and have good dispersion, but the magnetic properties are still not very high, such as the key index coercivity The force is only about 1000Oe

In addition, there are some documents (J. Appl. Phys, 2003, 93(10): 7589-7591 and Colloids & Surface A: Physicochem. Eng. Aspects, 2008, 313-314: 621-624) published the use of chemical synthesis methods Nano-samarium-cobalt permanent magnet particle method, but the samarium acetylacetonate and hydroxycobalt used in it are highly toxic substances, and the operation is very dangerous