六铁永久磁体中的粒度对齐是通过在室内和高温下进行压缩而实现的
Jacob L Valentin1, Frederik H Gjørup1,2, Cecilie G Knudsen1
1Department of Chemistry and Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Denmark. mch@chem.au.dk.
Nanoscale
|October 28, 2024
概括
热压缩显著改善了石六化永久磁铁的粒度对齐和磁性. 与冷压缩相比,这种方法提高了密度和纹理强度,克服了磁短路问题.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 磁力学 磁力学 是一种
背景情况:
- 斯特伦六化铁 (SrFe12O19) 是一个关键的永久磁铁材料.
- 实现高性能需要控制的粒度对齐 (纹理).
- 应用磁场通常用于诱导谷物对齐.
研究的目的:
- 为了研究在没有外部磁场的情况下,在石六聚中用于粒度对齐的形状控制前体.
- 为了比较冷和热压缩方法对纹理和磁性质的有效性.
- 了解磁性短路在压缩过程中的谷物对齐中的作用.
主要方法:
- 四个压缩系列:冷压 (CP),冷压接着烧结 (CPS),火花等离子烧结 (SPS) 和感应压 (IP).
- 在基里温度以下和以上进行的实验,以评估磁相互作用.
- 纹理的表征 (粒度对齐) 和残余磁化.
主要成果:
- 热压缩方法 (SPS,IP) 与冷压缩 (CP,CPS) 相比,产生了明显更清晰的纹理和更高的残余磁化.
- 热压缩样本与冷压缩样本的散装密度几乎翻了一番.
- 冷压缩显示较弱的纹理和较低的磁化,归因于粒子间的磁短路.
结论:
- 热压缩优于冷压缩,用于生产高性能六铁石磁铁.
- 形状控制的前体和热压缩使得无需应用磁场的粒度能够有效地对齐.
- 尽量减少磁短路对于实现强的纹理和磁性而言至关重要.
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