Bonded Rare Earth Permanent Magnets

Abstract

A bonded magnet is a generic term for composite permanent magnets obtained by solidifying and shaping various magnetic powders with a binder. Plastic magnets or “Pla-Mag” are synonyms. Magnetic properties themselves are inferior to sintered magnets because they contain a binder in addition to the magnet powder and fine pores remain after forming. However, because of its high degree of freedom of shape, it is possible to manufacture various near-net shape magnets with high accuracy such as thin-walled ring. It has also the characteristics that the toughness of the molded body is high, cracking is less likely to occur, and integral molding with a shaft or the like is possible. It is superior to sintered magnets in terms of being able to reduce core wobbling, etc., and many are used for small motors for electronic devices and the like.