揭示了 Nd-Fe-B 的高强制性,其梯度具有稀土丰富的相位大小
Dongmin Zhang1, Minggang Zhu1,2, Jingyan Zuo1
1Division of Functional Materials, Central Iron and Steel Research Institute, Beijing, 100081, China. mgzhu@126.com.
Materials horizons
|April 10, 2025
概括
研究人员发现了一种新方法,通过控制RERP尺寸梯度来增强稀土丰富相位 (RERP) 磁铁的强制性. 这种方法可以提高磁铁的性能,而无需依赖稀有元素,提供了具有成本效益的解决方案.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 磁力学 磁力学 是一种
背景情况:
- 提高永久磁铁强制性的传统方法通常依赖于昂贵的稀有元素,限制性能和可回收性.
- 微结构工程是关键,但目前的方法面临成本和材料限制.
研究的目的:
- 通过控制稀土丰富相位 (RERP) 尺寸,研究一种用于提高烧结磁体强制性的新方法.
- 为了实现更高的强制性,而不会影响Nd-Fe-B磁铁的残留性.
主要方法:
- 制造 (Nd0.7Pr0.3) 31Fe(球) M1B0.95 (M = Cu, Co, Al, Ga, wt%) 烧结磁铁,具有可控制梯度的RERP尺寸.
- 应用上下梯度应力 (压缩到拉力) 来诱导沿谷物边界的RERP迁移.
- 利用微磁模拟和磁光克尔效应测量来分析磁化逆转行为.
主要成果:
- 在不牺牲余量 (14.21 kGs) 的情况下,实现了高达14.91 kOe (11.60%高于对照) 的显著强制性增加.
- 观察到方向磁化逆转,由梯度RERP大小驱动,导致梯度去磁化场.
- 该研究表明,受控的RERP尺寸梯度对于增强磁性特性至关重要.
结论:
- 发现的方向磁化反转机制,与梯度RERP大小相关,为高性能永久磁铁提供了一条途径.
- 调节RERP尺寸分布对于优化Nd-Fe-B磁铁的强制性至关重要.
- 这种方法为传统方法提供了具有成本效益的替代方案,减少了对珍贵元素的依赖.
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