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DOE OSTI · 1637879

Neodymium-iron-boron magnet with selective surface modification, and method of producing same

Paranthaman, Mariappan Parans·McGuire, Michael A.·Parker, David S.·Rios, Orlando·Sales, Brian C.·Ucar, Huseyin·Mccall, Scott K.·McCallum, R. William·Nlebedim, Cajetan I.
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Abstract

A bulk high performance permanent magnet comprising a neodymium-iron-boron core having an outer surface, and a coercivity-enhancing element residing on at least a portion of said outer surface, with an interior portion of said neodymium-iron-boron core not having said coercivity-enhancing element therein. Also described herein is a method for producing the high-coercivity bulk permanent magnet, the method comprising: (i) depositing a coercivity-enhancing element on at least a portion of an outer surface of a neodymium-iron-boron core substrate to form a coated permanent magnet; and (ii) subjecting the coated permanent magnet to a pulse thermal process that heats said outer surface to a substantially higher temperature than an interior portion of said neodymium-iron-boron core substrate, wherein said substantially higher temperature is at least 200° C. higher than said interior portion and is of sufficient magnitude to induce diffusion of said coercivity-enhancing element below said outer surface but outside of said interior portion.

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BibTeXRIS

Paranthaman, Mariappan Parans, McGuire, Michael A., Parker, David S., Rios, Orlando, Sales, Brian C., Ucar, Huseyin, Mccall, Scott K., McCallum, R. William, Nlebedim, Cajetan I.. 2020-03-10. Neodymium-iron-boron magnet with selective surface modification, and method of producing same. https://www.osti.gov/biblio/1637879

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