RARE-EARTH PERMANENT MAGNET AND ROTARY MACHINE INCLUDING RARE-EARTH PERMANENT MAGNET

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It is intended to provide a permanent magnet usable in a rotary machine such as a permanent magnet-embedded electric motor, without deterioration in performance even when an external magnetic field exerting a demagnetization action is applied to the embedded permanent magnet. Disclosed are : a rare-earth permanent magnet-forming sintered body obtained by integrally sintering magnet material particles containing a rare-earth substance while shaping the magnet material particles, a rare-earth permanent magnet obtained by magnetizing the sintered body, and a rotary machine in which the permanent magnet is embedded. The rare-earth permanent magnet-forming sintered body is sectionalized into a widthwise central region, and first and second end regions located, respectively, on both sides of the central region. In the central region, easy magnetization axes of magnet material particles included in the central region are oriented in a direction substantially orthogonal to one surface of the sintered body extending in a width direction, and, in one or each of the first and second end regions, easy magnetization axes of magnet material particles included in the end region are oriented in directions along which they are converged such that a density of the magnet material particles whose easy magnetization axes are directed toward the one surface becomes greater in the end region than in the central region. In a magnet formed by this rare-earth permanent magnet-forming sintered body, a magnetic flux density in each of the end regions becomes greater than that in the central region, so that the deterioration in performance due to demagnetization is suppressed.