R-T-B RARE EARTH MAGNET POWDER, METHOD OF PRODUCING R-T-B RARE EARTH MAGNET POWDER AND BOND MAGNET

摘要

The present invention provides R-T-B-based rare earth magnet particles comprising no expensive rare resources such as Dy and having an excellent coercive force which can be produced by HDDR treatment without any additional steps. The present invention relates to R-T-B-based rare earth magnet particles comprising crystal grains comprising a magnetic phase of R 2 T 14 B, and a grain boundary phase, in which the grain boundary phase has a composition comprising R in an amount of not less than 13.5 atom% and not more than 35.0 atom% and Al in an amount of not less than 1.0 atom% and not more than 7.0 atom%. The R-T-B-based rare earth magnet particles can be obtained by controlling heat treatment conditions in the DR step of the HDDR treatment in the course of subjecting a raw material alloy to the HDDR treatment.