Evolution and process of manufacture of “NEO” magnets applied to motors of electric vehicles





Bonded, Permanent magnet, Rare earth, Sintered


After the development of Nd–Fe–B magnets, rare-earth magnets are now essential components in many fields of technology, because of their ability to provide a strong magnetic flux. There are two, well-established techniques for the manufacture of rare earth magnets: powder metallurgy is used to obtain high-performance, anisotropic, fully dense magnet bodies; and the melt-spinning or HDDR (hydrogenation, disproportionation, desorption and recombination) process is widely used to produce magnet powders for bonded magnets. In the industry of sintered Nd–Fe–B magnets, the total amount of production has increased and their dominant application has been changed to motors. In particular, their use for motors in hybrid cars is one of the most attractive applications. Bonded magnets have also been used for small motors, and the studies of nanocomposite and Sm–Fe–N magnets have become widespread. This paper reviews the current status and future trends in the research of permanent magnets.


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How to Cite

Abad, V., & Sagredo, J. (2018). Evolution and process of manufacture of “NEO” magnets applied to motors of electric vehicles. Revista De Metalurgia, 54(3), e127. https://doi.org/10.3989/revmetalm.127