Mössbauer study of treated Nd2Fe14B

Budzyński, Mieczysław; Constantin, Virgil C.; Popescu, Ana-Maria J.; Surowiec, Zbigniew; Tkachenka, Tamara M.; Yanushkevich, Kazimir I.

doi:10.1515/nuka-2015-0003

Abstract

The Nd₂Fe₁₄B cylindrical magnets were treated with water solutions of alkali, acid, and salt. Mössbauer spectroscopy was applied to study the composition and properties of the surface material of the treated magnets. It is shown that the main phase of the permanent Nd₂Fe₁₄B magnet partly decomposes. The released α-Nd at the grain boundaries interacts with water and forms neodymium hydroxide matrix, and the released Fe diffuses into it. The presence of Fe-Nd(OH)₃ is reflected in the paramagnet doublet in the Mössbauer spectra of treated neodymium magnets.

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Mössbauer study of treated Nd2Fe14B

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