Rare earth magnet, method for producing same and method for producing multilayer body

A rare earth magnet comprising:

• a magnet body containing a rare earth element;
• an amorphous layer formed on a surface of the magnet body and containing amorphous substance;
• and
• a protecting layer formed on a surface of the amorphous layer, wherein
• the magnet body is polycrystalline and contains polycrystal substance,
• a boundary between the magnet body and the amorphous layer includes a region where the polycrystal substance of the magnet body and the amorphous substance of the amorphous layer are mixed,
• the amorphous layer has a film thickness from 0.3 to 10 μm,
• the protecting layer consists of aluminum,
• the amorphous layer is amorphized from a surface of the magnet body and contains an element identical to a main component element of a magnet material contained in the magnet body,
• a roughness Ra of a boundary between the magnet body and the amorphous layer ranges from 1.27 to 1.45 μm,
• a roughness Ra of a boundary between the amorphous layer and the protecting layer ranges from 0.68 to 0.85 μm, and
• a coefficient of thermal expansion of the magnet body is substantially similar to a coefficient of thermal expansion of the amorphous layer.