Patent ID: 9076584
Filing Date: 2015-07-07
Classification: B22F,C21D,C22C,H01F

Abstract:
1. A powder compact used as a material for a rare-earth magnet comprising: a powder comprising: magnetic particles each containing a hydride of a rare-earth element in an amount of less than 40% by volume and the balance being Fe; a phase of the hydride of the rare-earth element is adjacent to a phase consisting of pure Fe, and an interval between adjacent phases of the hydride of the rare-earth element with the phase of Fe provided therebetween is 3 μm or less, wherein: the phase of the hydride of the rare-earth element is granular, the granular hydride of the rare-earth element is dispersed in the phase of Fe, the rare-earth element is Sm, and the hydride of the rare-earth element consisting of Sm and hydrogen, an antioxidation layer is provided on the surface of each of the magnetic particles, the antioxidation layer including a low-oxygen-permeability layer composed of a material having an oxygen permeability coefficient at 30° C. of less than 1.0×10 the low-oxygen-permeability layer is polyester or polyvinyl chloride, and the powder compact has a relative density of 85% or more.