在NaZn13型的La(Fe,Si,Co) 13化合物中,巨大的负热膨胀
Rongjin Huang1, Yanying Liu, Wei Fan
1Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, China.
Journal of the American Chemical Society
|July 27, 2013
概括
,Fe,Si) 13化合物具有负热膨胀 (NTE),对工业应用很有用. 优化成分,特别是,扩大了NTE窗口,并提高了其在室温应用的潜力.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 基于La,Fe,Si) 13的化合物是已知的磁热性材料.
- 这些材料在基里温度附近显示显著的负热膨胀 (NTE).
- 它们对工业NTE应用的潜力尚未得到充分探索.
研究的目的:
- 合成和研究NaZn13型LaFe13-xSix和LaFe11.5-xCoxSi1.5化合物的线性NTE特性.
- 为了优化化学成分,增强NTE特性.
- 评估这些化合物作为工业用途的NTE材料的潜力.
主要方法:
- 合成NaZn13类型的LaFe13-xSix和LaFe11.5-xCoxSi1.5化合物. 这些化合物包括:
- 通过构成优化研究线性负热膨胀 (NTE) 特性.
- 通过调整 (Co) 兴奋剂水平来调整NTE特征.
主要成果:
- 优化的化学成分成功地将急剧的体积变化转化为持续膨胀.
- 增加的 (Co) 含量将NTE转移到更高的温度,并扩大了操作窗口.
- 拉费10.5Co1.0Si1.5化合物在110 K范围 (240350 K),包括室温,呈现出26.1 × 10(-6) K(-1的线性NTE系数.
结论:
- 基于La (Fe,Si) 13的化合物的受控组成允许可调节的NTE特性.
- 显著的NTE和广泛的操作窗口表明潜在的工业应用.
- 这些材料显示出作为有效的NTE材料的前景,特别是用于室温应用.
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