物理化学学报 >> 2000, Vol. 16 >> Issue (01): 9-14.doi: 10.3866/PKU.WHXB20000103

研究论文 上一篇    下一篇

液态结构与Al-Fe-Ce合金短程有序的相关性

张林, 吴佑实, 边秀房, 李辉   

  1. 山东工业大学材料科学与工程学院,济南 250061
  • 收稿日期:1999-04-05 修回日期:1999-05-05 发布日期:2000-01-15
  • 通讯作者: 张林

Correlation between Liquid Structure and the Chemical Short-range Order of Al-Fe-Ce Amorphous Alloy

Zhang Lin, Wu You-Shi, Bian Xiu-Fang, Li Hui   

  1. College of Materials Science and Engineering,Shandong University of Technology,Jinnan 250061
  • Received:1999-04-05 Revised:1999-05-05 Published:2000-01-15
  • Contact: Zhang Lin

摘要:

采用X射线衍射技术研究了Al_0.9Fe_0.1和Al_0.9Fe_0.05Ce_0.05合金的液态结构及Al_0.9Fe_0.05Ce_0.05合金的非晶结构,并采用DSC热分析研究了非晶合金的晶化行为.发现液态和非晶态合金的结构因子曲线上都存在明显的预峰,所对应的化学短程有序结构随温度降低,尺寸不断增大,但其结构单元的尺寸保持不变.Ce的加入使液态合金中化学短程有序及其结构单元的尺寸增大,并有利于原子间交互作用增强,从而提高非晶形成能力.预峰所对应的化学短程有序结构单元是以Fe原子为中心的二十面体准晶结构,这种结构在液态已形成,并保留在非晶中.

关键词: Al-Fe-Ce非晶合金, 预峰, 化学短程有序, 结构因子

Abstract:

The liquid structures of Al_0.9Fe_0.1 and Al_0.9Fe_0.05Ce_0.05 alloys and the microstructure of the Al_0.9Fe_0.05Ce_0.05 amorphous alloy have been studied by X-ray diffraction (XRD), and the crystallization behavior of the amorphous alloy has been investigated by differential scanning calorimetry (DSC). The distinct prepeaks have been found from the structure factors of the liquid and amorphous alloys. The structural size of chemical short-range order (CSRO) corresponding to the prepeak increases with decreasing temperature, but its structural unit size remains constant. The addition of Ce can increase the structural size of CSRO and its unit size, and improve the interaction between atoms, so it is helpful to the Al-based glass formability. The structural unit corresponding to the prepeak is an icosahedral quasicrystalline structure with a Fe atom as the interstitial atom, and this structure has already formed in the liquid alloy and can be reserved in the amorphous alloy.

Key words: Al-Fe-Ce amorphous alloy, Prepeak, Chemical short-range order, Structure factor