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Temperature stability of SmCo (2:17) magnets modified by Ni–Cr two-layer coating

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Abstract

The oxidation resistance behavior of SmCo (2:17)-type high-temperature magnets modified with Ni–Cr two-layer coating was studied. The study depicts the mass gain kinetics and magnetic properties of uncoated and Ni–Cr-modified magnets oxidized at high temperature (500 °C) in air for 200 h. The oxidation test results illustrate that the mass gain of uncoated magnet is 6.95 mg·cm−2 which is more than that (0.08 mg·cm−2) of coated magnet after 200 h. For the magnetic properties concerned, there is a great loss for uncoated magnet, while for coated magnet, magnetic properties do not change much. The study of uncoated magnet through X-ray diffraction (XRD) and electron probe microanalysis (EPMA) shows that the invasion of oxygen at high temperature leads to the loss of magnetic properties by changing the microstructure of magnet.

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Acknowledgements

This work was financially supported by the National Science Foundation of China (No. 51471016) and the Natural Science Foundation of Beijing (No. 2151002).

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Authors and Affiliations

  1. School of Materials Science and Engineering, Beihang University, Beijing, 100191, China

    Saira Bibi, Jing-Min Wang & Cheng-Bao Jiang

  2. National Center of Physics, Quaid-e-Azam University, Islamabad, 45320, Pakistan

    M. Faisal Rathore

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  1. Saira Bibi
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  2. Jing-Min Wang
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  3. M. Faisal Rathore
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  4. Cheng-Bao Jiang
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Correspondence to Jing-Min Wang.

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Bibi, S., Wang, JM., Faisal Rathore, M. et al. Temperature stability of SmCo (2:17) magnets modified by Ni–Cr two-layer coating. Rare Met. 38, 238–244 (2019). https://doi.org/10.1007/s12598-018-1076-0

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  • DOI: https://doi.org/10.1007/s12598-018-1076-0

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