Rare earth element permanent magnet material
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsHideharu Nobutoki, Suguru Nagae, Satoru Hayasi
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Abstract
A material for a rare earth permanent magnet having a high magnetic coercive force and a high residual magnetic flux density. 28 to 35% by weight of at least one rare earth element selected from the group consisting of neodymium, praseodymium, dysprosium, terbium, and holmium, 0.9 to 1.3% by weight of boron, 0.25 to 3% by weight of phosphorus, iron, and inevitable impurities. It can further comprise 0.1 to 3.6% by weight of cobalt and 0.02 to 0.25% by weight of copper.
Claims12
A rare earth permanent magnet material comprising 28 to 35% by weight of at least one rare earth element selected from the group consisting of neodymium, praseodymium, dysprosium, terbium, and holmium, 0.9 to 1.3% by weight of boron, 0.25 to 3% by weight of phosphorus, and iron, having a residual magnetic flux density of 11 to 18 kG, a magnetic coercive force of 14 to 21 kOe at 25° C., and produced by sintering at a temperature in a range from 1,0000° C. to l,4000° C.
A rare earth permanent magnet material consisting essentially of 28 to 35% by weight of at least one rare earth element selected from the group consisting of neodymium, praseodymium, dysprosium, terbium, and holmium, 0.9 to 1.3% by weight of boron, 0.25 to 3% by weight of phosphorus, 58 to 80% by weight of iron, 0.1 to 3.6% by weight of cobalt, and 0.02 to 0.25% by weight of copper, and having a residual magnetic flux density of 11 to 18 kG, a magnetic coercive force of 14 to 21 kOe at 25°C.
Dependencies are inferred from the claim text.