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| Corrosion behavior and mechanism of bonded NdFeB magnets |
| XIAO Kai-ye，XU Hai，ZHENG Xiao-jing，ZHENG Wen，GUO Zhi-wei |
| （Institute of Physical and Chemical Engineering of Nuclear Industry， Tianjin 300180， China） |
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Abstract As a permanent magnet material with high magnetic energy product， bonded NdFeB magnets have been widely used in aerospace， nuclear industry， transportation and other fields. Its raw material is NdFeB rapid quenching powder. The NdFeB magnets are easy to corrode in air environment， in order to ensure the reliability and life of bonded NdFeB magnets， the corrosion behavior of magnets with corrosion defect after protective treatment was studied. It is found that the corrosion grows continually and the magnetic performance decreases even though the magnet has reliable coating protection. The corrosion rates of magnets with different damage degrees are different. With the increase of corrosion time， the previous corrosion product Fe2O3 reacts with water to produce H2， accelerating the corrosion of damaged magnets.
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Received: 10 April 2017
Published: 12 October 2018
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2018, Vol. 28 
