热变形Nd-Fe-B磁铁的重大进展:一个审查
Renjie Chen1,2,3, Xianshuang Xia1,2, Xu Tang1,2
1CISRI & NIMTE Joint Innovation Center for Rare Earth Permanent Magnets, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Materials (Basel, Switzerland)
|July 14, 2023
概括
热变形 (HD) Nd-Fe-B磁铁为新能源汽车提供了潜力,但其强制性低于预期. 本综述探讨了颗粒边界扩散和双合金扩散过程,以提高这些磁体的强制性.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 工程 工程师 工程师 工程师
背景情况:
- 高性能Nd-Fe-B磁铁对于新能源汽车的引电机至关重要.
- 不同类型的热变形 (HD) Nd-Fe-B 磁铁具有细粒度 (200-400 nm),但强制性低于预测.
- 与Nd2Fe14B相异性场相比,这种低性能限制了它们的全部潜力.
研究的目的:
- 综合审查高清Nd-Fe-B磁铁的基本原理和发展.
- 研究和总结谷物边界扩散工艺 (GBDP) 和双合金扩散工艺 (DADP) 的进展.
- 讨论强制性增强的机制,并分析磁化逆转行为.
主要方法:
- 全球关于高强度Nd-Fe-B磁铁的科学研究的综述.
- 调查GBDP和DADP最近的进展情况.
- 微磁模拟以了解结构-属性关系.
- 磁光克尔效应显微镜用于分析磁化逆转.
主要成果:
- 高清磁铁具有细粒度,但强制性低于最佳.
- GBDP 和 DADP 是加强强制性的关键策略.
- 微磁模拟揭示了改善强制性的机制.
- 磁化逆转分析确定了微观结构弱区域.
结论:
- 对GBDP和DADP的进一步研究对于释放HD Nd-Fe-B磁铁的全部潜力至关重要.
- 通过模拟和显微镜了解结构属性关系对于有针对性的改进至关重要.
- 优化高清Nd-Fe-B磁铁将大大有利于新能源汽车技术.
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