Rare earth permanent magnet material and preparation process thereof

Abstract

The invention provides an rare earth permanent magnet material and a preparation process thereof. According to the invention, specific permanent magnet alloy powder limited by the ratio of each element is adopted, and an unique binder resin composition is adopted for special granulation, molding and coating treatment to obtain a bonded rare earth permanent magnet material, so that the bonded rareearth permanent magnet material has the advantages of low cost, high temperature resistance, corrosion resistance, excellent magnetizing performance and the like, and the use reliability, stability and wide applicability of the rare earth permanent magnet material are ensured.

Description

technical field [0001] The invention relates to the technical field of magnetic materials, in particular to a bonded rare earth permanent magnet material with low cost, high temperature resistance and excellent magnetization. Background technique [0002] Rare earth permanent magnet materials are permanent magnet alloy materials with intermetallic compounds composed of different rare earth elements and transition group metal elements (Fe, Co, Ni, etc.) as the main phase. Since it was invented in the 1960s, rare earth permanent magnet materials have developed rapidly and have been widely used in many fields. They have become important basic functional materials for contemporary new technologies, especially in the field of permanent magnet motors. effect. Nowadays, rare earth permanent magnet motors have covered various main types such as stepping motors, brushless motors, servo motors and linear motors, and are widely used in computers, printers, household appliances, air-co...

AI Technical Summary

Problems solved by technology

[0005] However, since the NdFeB permanent magnet powder used in bonded NdFeB rare earth permanent magnets usually produces microcracks in the magnetic powder particles during the refining and crushing process, resulting in an active surface, it is very easy to oxidize and corrode, so that in the subsequent use process It is easy to cause rapid oxidation and corrosion to cause a sharp drop in magnetic properties, especially in the preparation process of compression molding, it is easier to cause new microcracks and the continuous expansion of original microcracks due to compression

At the same time, thermosetting resins used as binders are usually prone to softening and thermal expansion in high-temperature environments, which in turn causes a series of problems such as the reduction of high-temperature mechanical strength and magnetic properties of bonded NdFeB rare earth permanent magnets.

As mentioned earlier, after forming and curing, it is usually necessary to coat the surface with an anti-corrosion film to solve problems such as anti-corrosion and thermal demagnetization, but this will increase many process steps and a lot of cost