埃尔:在2种:17型永磁铁中,同时实现卓越的温度稳定性和高磁性质的关键:
Zan Long1, Chaoyue Zhang2, Yuqing Li1
1College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Ministry of Education of China, Beijing University of Technology, Beijing 100124, China. yueming@bjut.edu.cn.
Materials horizons
|January 23, 2025
概括
新的稀土基磁铁为精密仪器提供了卓越的温度稳定性和高性能. 这些先进的永久磁铁具有出色的磁能产品和强制性,满足苛刻的工业需求.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 磁力学 磁力学 是一种
背景情况:
- 精密仪器需要具有高能量密度,温度稳定性,磁能产量 ((BH) max) 和强制性 (Hcj) 的永磁体.
- 现有的稀土磁铁在满足这些综合需求方面存在局限性,特别是温度稳定性.
研究的目的:
- 设计和开发具有增强综合性磁性性能的新型稀土基磁铁 (2:17型磁铁).
- 为了研究成分,特别是和含量对磁性性能和温度稳定性的影响.
主要方法:
- (Er, Sm) ((Co, Fe, Cu, Zr) 7.6 稀土磁铁的组成设计.
- 阶段过渡分析以了解结构发展.
- 在温度范围 (20-150°C) 上,磁性属性表征,包括残余 (Br),强制性 (Hcj) 和最大能量产物 ((BH) max).
主要成果:
- 基于的2:17型磁铁在Br和 (BH) max中表现出优越的温度稳定性,这是由于独特的温度补偿和高和磁化.
- 部分替代萨马促进了所需的细胞结构,增强了强制性.
- 最佳的组成 (60% Er) 为 Br 和 (BH) max 产生接近零的温度系数, Br = 8.92 kG, Hcj = 29.83 kOe, 和 (BH) max = 18.5 MGOe 在 20-150 °C.
结论:
- 开发的2:17型Er磁铁表现出了卓越的综合磁性,包括出色的温度稳定性和高磁性性能.
- 这些发现为开发下一代永久磁铁提供了宝贵的见解,适用于精密仪器中的先进应用.
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