由于二极相互作用,SrFe12O19/Fe交换脱的硬软复合磁铁的留存增加
Jesús Carlos Guzmán-Mínguez1, Cecilia Granados-Miralles1, Patrick Kuntschke2
1Electroceramic Department, Instituto de Cerámica y Vidrio, CSIC, 28049 Madrid, Spain.
Nanomaterials (Basel, Switzerland)
|July 29, 2023
概括
开发新的永久磁铁至关重要. 这项研究探讨了基于铁的复合材料,揭示了双极相互作用,增强了磁性,为稀土磁铁提供了有希望的替代品.
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:
- 稀土磁铁面临着地缘战略和环境挑战.
- 硬软磁性复合材料提供了潜在的替代品,但取得了有限的成功.
- 基于铁 (SrFe12O19) 的复合材料正在研究改善磁性特性.
研究的目的:
- 了解基于铁的硬软复合材料中的磁性和微观结构性质之间的相关性.
- 调查软相 (Fe粒子) 含量和尺寸对磁性质的影响.
- 探索硬 (SFO) 和软 (Fe) 阶段之间的相互作用机制.
主要方法:
- 合成具有不同Fe颗粒含量和尺寸 (纳米和微米大小) 的铁 (SFO) 陶.
- 制造粉末和密集的注射成型磁铁.
- 磁性和微观结构性质的表征.
- 微磁模拟用于分析相间相互作用.
主要成果:
- 在复合材料中测量了高于预期的余量,尽管Fe和SFO之间没有交换合.
- 与纯铁素磁铁相比,注射成型的异性磁铁在残留量上有2.4%的改善.
- 双极相互作用被确定为负责将一部分软相旋转与硬相磁化对齐的机制.
结论:
- 这项研究阐明了基于铁的硬软复合材料中的二极相互作用机制.
- 这种相互作用导致增强的磁性,特别是残留.
- 这些发现为开发新型,高性能永久磁铁提供了洞察力,作为稀土基材料的替代品.
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