ALLOY FOR R-T-B-BASED RARE EARTH SINTERED MAGNET, PROCESS OF PRODUCING ALLOY FOR R-T-B-BASED RARE EARTH SINTERED MAGNET, ALLOY MATERIAL FOR R-T-B-BASED RARE EARTH SINTERED MAGNET, R-T-B-BASED RARE EARTH SINTERED MAGNET, PROCESS OF PRODUCING R-T-B-BASED RARE EARTH SINTERED MAGNET, AND MOTOR

摘要

An alloy for R-T-B-based rare earth sintered magnets which contains R which is a rare earth element; T which is a transition metal essentially containing Fe; a metallic element M containing one or more metals selected from Al, Ga and Cu; B and inevitable impurities, in which R accounts for 13 at % to 15 at %, B accounts for 4.5 at % to 6.2 at %, M accounts for 0.1 at % to 2.4 at %, T accounts for balance, a proportion of Dy in all rare earth elements is in a range of 0 at % to 65 at %, and the following Formula 1 is satisfied,;0.0049Dy+0.34≦B/TRE≦0.0049Dy+0.36   Formula 1 ;wherein Dy represents a concentration (at %) of a Dy element, B represents a concentration (at %) of a boron element, and TRE represents a concentration (at %) of all the rare earth elements.

主权项

1. An R-T-B-based rare earth sintered magnet comprising:
R which is a rare earth element; T which is a transition metal essentially comprising Fe; a metallic element M comprising one or more metals selected from Al, Ga and Cu; B; and inevitable impurities, wherein R accounts for 13 at % to 15 at %, B accounts for 4.5 at % to 6.2 at %, M accounts for 0.1 at % to 2.4 at %, T accounts for balance, a proportion of Dy in all rare earth elements is in a range of 0 at % to 65 at %, the following Formula 1 is satisfied, which is made of a sintered body including a main phase primarily comprising R2Fe14B and a grain boundary comprising more R than the main phase, in which the grain boundary phase includes a phase having a concentration of all atoms of the rare earth elements of 70 at % or more and a phase having a concentration of all the atoms of the rare earth elements in a range of 25 at % to 35 at %,
0.0049Dy+0.34≦B/TRE≦0.0049Dy+0.36   Formula 1 wherein Dy represents a concentration (at %) of a Dy element, B represents a concentration (at %) of a boron element, and TRE represents a concentration (at %) of all the rare earth elements.