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Investigating the properties of recycled NdFeB magnets

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Abstract

We report investigations on the processing by Spark Plasma Sintering (SPS) of RE2Fe14B (RE = Nd, Pr…) powders obtained by hydrogen decrepitation of decommissioned magnets and the magnetic properties of the consolidated magnets. First experiments have been carried out with a commercial powder to make clear the mechanisms occurring during the powder densification. The magnetic properties of the sintered bulks were measured to determine the SPS cycle resulting in the best saturation and remanent magnetization (Ms and Mr, respectively), coercive field (Hc) and stored magnetic energy (BHmax product). The optimized cycle was subsequently applied to a recycled powder. The properties of the magnets obtained after processing the recycled powder are compared to those made with the commercial one.

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Authors and Affiliations

  1. Normandie University, ENSICAEN, UNICAEN, CNRS, CRISMAT, Caen, France

    Pierre Bernstein, Y. Xing & Jacques Noudem

  2. Université Grenoble Alpes, CNRS, Institut Néel, Grenoble, France

    Sophie Rivoirard

  3. Valeo Powertrain Systems, Créteil, France

    Jean-Marc Dubus

Authors
  1. Pierre Bernstein
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  2. Y. Xing
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  3. Jean-Marc Dubus
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  4. Sophie Rivoirard
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  5. Jacques Noudem
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Corresponding author

Correspondence to Pierre Bernstein.

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Bernstein, P., Xing, Y., Dubus, JM. et al. Investigating the properties of recycled NdFeB magnets. Eur. Phys. J. Spec. Top. 231, 4179–4183 (2022). https://doi.org/10.1140/epjs/s11734-022-00662-y

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  • DOI: https://doi.org/10.1140/epjs/s11734-022-00662-y

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