连续的磁转换使 (Hf,Ti) Fe2+x中零热膨胀的超宽温度窗口成为可能
Zhao Pan1, Haowei Zhou2, Chao Chen1,3
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P.R. China.
零热膨胀 (ZTE) 合金现在在极宽的温度范围内工作. 这一 (Hf,Ti) Fe2+x金属磁铁的突破将精确的应用范围扩展到500K之外.
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:
- 零热膨胀 (ZTE) 材料对于精密工程至关重要.
- 目前的ZTE合金具有有限的操作温度范围,通常低于500K.
- 开发高温ZTE材料仍然是一个重大挑战.
研究的目的:
- 为了在超宽温度范围内实现金属磁铁的零热膨胀.
- 为了研究高温ZTE背后的机制,在非静电测量Kagome金属.
- 探索 (Hf,Ti) Fe2+x合金在先进应用中的潜力.
主要方法:
- 非静电 (Hf,Ti) Fe2+x合金的高温回火.
- 使用磁化测量,洛伦兹传输电子显微镜 (TEM),中子粉 difraktion 和 Mössbauer 光谱法进行表征.
- 分析热膨胀特性和磁性过渡.
主要成果:
- 在Hf0.6Ti0.4Fe2.54中达到ZTE,热膨胀的平均线性系数为0.76 × 10^-6 K^-1,从112 K到525 K.
- 观测到连续的磁转换,包括在370 K附近的旋转重定向和在525 K左右的偏磁转换.
- 识别了反地铁作为引入磁交换相互作用和稳定磁顺序的关键因素.
结论:
- 不同质的元素分布和多个磁顺序使得 (Hf,Ti) Fe2+x中的超宽温度ZTE成为可能.
- 磁性顺序和音声效应之间的补偿对观察到的ZTE行为负责.
- 这项研究提供了对高温应用金属磁铁中非传统ZTE机制的见解.
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