处理驱动的化学排序及其对高合金磁性特性的影响
V Chaudhary1, S Dasari2, A Sharma3
1Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-41296, Sweden. varunc@chalmers.se.
Faraday discussions
|October 6, 2025
概括
在AlTiCoCrFeNi高合金 (HEAs) 中的化学排序显著影响磁性. 微观结构的变化改变了沉物演变,影响了低温下的磁过渡和强制性.
科学领域:
- 材料科学 材料科学 材料科学
- 磁力学 磁力学 是一种
- 物理金学 物理金学
背景情况:
- 高合金 (HEA) 为高级应用提供可调节的性能.
- 了解HEAs中微观结构和磁性行为之间的相互作用对于材料设计至关重要.
研究的目的:
- 研究化学排序及其长度尺度对Al$_{0.2}$Ti$_{0.3}$Co$_{1.5}$CrFeNi$_{1.5}$HEA的磁性行为的影响.
- 在不同的加工条件下将微观结构进化与磁性相关联.
主要方法:
- 通过溶液回火,750°C回火,冷加回火来改变微观结构条件.
- 描述沉物演变 (体积分数,大小,形态) 和阶段形成 (L1$_{2}$,L2$_{1}$).
- 从2K到300K进行磁性测量,以确定和磁化,强制性和磁性过渡温度.
主要成果:
- 溶液化条件显示,单一的磁过渡在48K附近,具有低强制性,与微细的L1$_{2}$沉物相关.
- 在冷和冷条件下,由于L1$_{2}$相粗化和脱,呈现出第二次低温磁性过渡.
- 处理条件中的强制性增加归因于域壁钉和L2$_{1}$阶段的存在.
结论:
- 化学排序和微观结构的演变是这个HEA系统中低温磁性行为的关键决定因素.
- 定制加工路径可以控制多功能HEAs中的磁性特性.
- 这些发现有助于更好地了解磁性HEAs,这些HEAs具有结合磁性和机械性能的潜力.
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