CRUSHING SYSTEM, METHOD FOR MANUFACTURING R-T-B TYPE PERMANENT MAGNET AND R-T-B TYPE PERMANENT MAGN

PROBLEM TO BE SOLVED : To provide a crushing apparatus by which a permanent magnet of stable quality can be mass-produced in high manufacturing efficiency. SOLUTION : 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.