稀土铈提高钕铁硼磁体的耐腐蚀性。

Rare Earth Cerium Increases the Corrosion Resistance of NdFeB Magnets.

作者信息

Dai Jialei, Yang Zixuan, Liu Qian

机构信息

Key Laboratory of Impact and Safety Engineering, Ministry of Education, Ningbo University, Ningbo 315211, China.

Key Laboratory of the Ministry of Education for Modern Metallurgy Technology, North China University of Science and Technology, Tangshan 063210, China.

出版信息

Materials (Basel). 2020 Sep 30;13(19):4360. doi: 10.3390/ma13194360.

DOI:10.3390/ma13194360

PMID:33008029

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7579091/

Abstract

Herein, we investigated the effects of Ce on the corrosion behavior of NdFeB magnets in 3.5% NaCl solutions using electrochemical tests, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) mapping, and scanning Kelvin probe force microscopy (SKPFM). We demonstrated that Ce markedly enhances the corrosion resistance of NdFeB magnets. Ce primarily replaces Nd in the Nd-rich phase instead of matrix phase, increasing the surface potential of the Nd-rich phase. An increase in the Ce content from 0 to 5.21 wt%, decreased the potential difference between the main phase and (Nd, Ce)-rich phase from 350.2 mV to 97.7 mV; therefore, the corrosion resistance of the magnetic materials increased. The corrosion resistance constituted the Nd-rich phase < the void < metal matrix. Moreover, based on the results of the study, we discussed the impact mechanism of additions of Ce on the corrosion resistance of the magnets.

摘要

在此，我们使用电化学测试、扫描电子显微镜（SEM）、能量色散光谱（EDS）映射和扫描开尔文探针力显微镜（SKPFM）研究了铈对钕铁硼磁体在3.5%氯化钠溶液中的腐蚀行为的影响。我们证明，铈显著提高了钕铁硼磁体的耐腐蚀性。铈主要取代富钕相中的钕而非基体相，增加了富钕相的表面电位。铈含量从0增加到5.21 wt%，主相和富（钕，铈）相之间的电位差从350.2 mV降至97.7 mV；因此，磁性材料的耐腐蚀性增加。耐腐蚀性由强到弱依次为富钕相＜空隙＜金属基体。此外，基于研究结果，我们讨论了添加铈对磁体耐腐蚀性的影响机制。