Powder Surface Modification as a Method of Corrosion Rate Limitation of the Magnetic RE-M-B Composite in an Acid Medium with Different pH

Powder Surface Modification as a Method of Corrosion Rate Limitation of the Magnetic RE-M-B Composite in an Acid Medium with Different pH

KLIMECKA-TATAR Dorota

Abstract. This paper presents the results of research on the effects of chemical treatment of the magnetic powder particles surface on the corrosion resistance of composites based on Nd12Fe77Co5B6 powder bonded with an epoxy resin. In the studies, a magnetic material formed of a commercial MQP-B powder has been used and subjected to chemical modification in such aqueous solutions as acetic acid, EDTA, citric acid and oxalic acid. Chemical treatment of the powder particles surface was applied for etching the oxide paramagnetic phases formed on the surface as an effect of spontaneous oxidation of the alloy elements (Nd and Fe) in the presence of oxygen and moisture. On the basis of changes in the polarization resistance value, which were recorded for a series of samples in 0.5M acidic sulphate solutions (pH = 2, 3 and 4), it has been found that the proposed pre-treatment has beneficial effect on the stability of the material in acid environments.

Keywords
Bonded Magnets, Nd-Fe-B Alloys, Polarization Resistance

Published online 7/16/2018, 6 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: KLIMECKA-TATAR Dorota, ‘Powder Surface Modification as a Method of Corrosion Rate Limitation of the Magnetic RE-M-B Composite in an Acid Medium with Different pH’, Materials Research Proceedings, Vol. 5, pp 231-236, 2018

DOI: https://dx.doi.org/10.21741/9781945291814-41

The article was published as article 41 of the book Terotechnology

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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