Disintegrating system, permanent magnet and manufacturing method thereof

Abstract

Provided is a crushing apparatus by which a permanent magnet of stable quality can be mass-produced in high manufacturing efficiency.This R-T-B type permanent magnet consists of a sintered compact containing a main phase consisting of a R2T14B phase (wherein R is one or more rare earth elements and contains Y; T is one or more transition metal elements and contains Fe or Fe and Co as essential ones) and a grain boundary phase containing R of the amount more than that of the main phase. A crusher 20 to be used when the R-T-B type permanent magnet is manufactured is constituted so that an alloy being a raw material is crushed by making the alloy collide with a collision plate 207 in an inner cylinder 202 by a carrier gas spouted vertically upward from the bottom end of an outer cylinder 201 and the crushed alloy is classified by a classification rotor 210 arranged in the upper part of the cylinder 202. The particle size distribution of the fine particles obtained by the crusher 20 can be measured by an on-line particle size distribution measuring instrument 60.

Description

technical field [0001] The present invention relates to a crushing system used in the production process of rare earth permanent magnets, a production method of R-T-B permanent magnets, and the like. Background technique [0002] In rare earth permanent magnets, R (R is one or more than two rare earth elements containing Y), T (T is one or two or more transition metal elements with Fe and Co as essential elements) and R-T-B-based permanent magnets with B (boron) as the main component have excellent magnetic properties, and Nd as the main component is abundant in resources and relatively low in price, so the demand is increasing year by year. In order to improve the magnetic properties of R-T-B permanent magnets, intensive research and development are also being carried out (for example, refer to Patent Document 1). [0003] Patent Document 1: JP-A-1-219143 (page 1). [0004] However, in order to increase the performance of the above-mentioned R-T-B permanent magnet, it is ...

AI Technical Summary

Problems solved by technology

Normally, sampling can be easily performed by taking out the container provided in the system to the outside of the system. However, when the system is in a hypoxic or anaerobic state, it is not preferable from the viewpoint of maintaining the hypoxic or anaerobic state. Opening and closing valves, etc. to take out the container, etc., and because the activity of the obtained fine powder is extremely high, it is difficult to perform sampling to take the fine powder out of the system

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