Rare RD iron boron permanent magnet and manufacturing process

Disclosed is a method for the preparation of a novel composite rare earth-based magnetically anisotropic sintered permanent magnet in which : (a) a base alloy consisting of a host phase of R2T14B (R : a rare earth element; T : iron or a combination of iron and cobalt) having a particle diameter of 2 to 10 mu m and containing in each particle a phase rich in the content of T and having a particle diameter not exceeding 1 mu m is prepared by the strip casting method; (b) the base alloy is crushed; (c) the base alloy powder is blended in a specified proportion with a powder of an auxiliary alloy of R-T or R-T-B in a specified proportion; (d) the powder blend is subjected to further comminution; (e) the comminuted powder blend is subjected to compression-molding in a magnetic field into a powder compact; and (f) the powder compact is sintered by a heat treatment.