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

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Provided is a permanent magnet that does not undergo performance reduction in a rotary machine, such as a permanent magnet-embedded electric motor, even when an external magnetic field that causes demagnetization of the embedded permanent magnet is applied. Disclosed are : a rare-earth permanent magnet-forming sintered compact made by integrally sintering and molding magnet material particles including a rare-earth substance; a rare-earth permanent magnet obtained by magnetizing said sintered compact; and a rotary machine in which said magnet is embedded. This rare-earth permanent magnet-forming sintered compact is partitioned into a central region in the width direction, and first and second end-section regions located on respective sides of the central region. In the central region, the axis of easy magnetization of magnet material particles included in the central region is oriented in a substantially perpendicular direction to one surface of a sintered compact section that extends in the width direction. In the first end-section region and/or the second end-section region, the axis of easy magnetization of the magnet material particles included in said region(s) is oriented in a direction that converges such that the density of the magnet material particles directed toward said one surface becomes higher than that in the central region. A magnet formed by this rare-earth permanent magnet-forming sintered compact has a higher magnetic flux density in the end-section regions than in the central region, and performance reduction caused by demagnetization is suppressed.