SINTERED BODY FOR FORMING RARE EARTH MAGNET, AND RARE EARTH PERMANENT MAGNET OBTAINED BY MAGNETIZIN

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The present invention obtains a sinusoidal surface flux distribution at the gap positions between end faces in a magnet in which a plurality of magnets are disposed end to end. Provided is a sintered body for forming a rare earth magnet that comprises a co-fired structure of magnetic material particles including a rare earth substance. The co-fired structure has a three-dimensional shape having a transverse cross-section with a shape that comprises : a radial direction outer-side arc-shaped surface having a first curvature radius; a radial direction inner-side arc-shaped surface having a second curvature radius which is smaller than the first curvature radius, and having an arc-shape which is concentric to the outer-side arc-shaped surface; and a first end face and a second end face which are radial direction faces along an imaginary radial line extending from the circle center of the arc shape. The three-dimensional shape also has axial direction length in an orthogonal direction to the transverse cross-section. The outer-side and inner-side arc-shaped surfaces each have a circumferential direction length corresponding to an angle range 2ω formed by two imaginary radial lines that define the respective first and second end faces. Upon a center radial line connecting the circle center and the circumferential-direction center point of the outer-side arc-shaped surface, the easy axis of the magnetic material is oriented outward in the radial direction along the center radial line. At a position upon an arbitrary radial line which is in a position that is an angle θ from the center radial line within a center region 2(1 - ε)ω which excludes end regions defined as the regions extending to an angle range εω from the first and second end faces, the easy axis is oriented to a direction displaced, relative to the arbitrary radius, from the direction oriented outward in the radial direction to extent of only an angle Φ in the center radial line direction. In the end regions, the easy axis is oriented to a direction displaced at least 5° further than the angle Φ outward in the radial direction. Herein, ε is 0.1 ≤ ε ≤ 0.6, the angle Φ is an angle defined by the formula Φ = (90° - d) ⋅ θ / ω, and d is a constant defined by an angle within the range of 0° < d ≤ 5° .