Abstract
Using aθ-θ X-ray diffractometer the structure of liquid hypoeutectic Al-Fe alloy at 675°C and its change with different thermal histories are investigated. Liquid Al is used as a reference system. It is found that a pre-peak appears on the small angle part of the structure factor of the nonsuperheated hypoeutectic Al-Fe alloy, but disappears after superheating whereas the structure factors of liquid Al hardly change with the different thermal histories, and no pre-peak can be observed on them. The appearance of a pre-peak is a mark of the intermediate-range order (IRO). The pre-peak is taken as the correlation between Fe atoms on the IRO length scale. Assume that the crystalline structure is the first-order approximation of the liquid structure. A model structure is constructed. The basic unit Is a cube formed by 8 Al atoms on its corner and one Fe atom occupying its center. The translation of such a unit along its fourbody diagonals by the length of a diagonal can meet the requirement of the Fe-Fe distance and glves a DO3-like structure. If the vacancy among the units is filled with fcc-like Al cells, the composition of the entity is about Al7,Fe, close to that of the metastable phase Al6Fe from rapid solidification. It is speculated that there are Al6,Fe-like clusters in the liquid hypoeutectic Al-Fe alloy.
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References
Chen, L. Q., Shen, N. F., Sun, G. X., Formation conditions of massive phase in rapidly-solidified A-Fe-V-Si alloy,Acta Metallurgica Sinica, 1995, 31B(7): 296.
Narayman, A. L., Sumuel, F. H., Gruzleski, J. E., Crystallization behavior of iron-containing intermetallic compounds in 319 aluminum alloy,Metall. Mater. Trans., 1994, 25A: 1761.
Manh, D. N., Mayu, D., Pasture, A.et al., Electronic structure and hybridition effects in transition-metal-polyvalentmetal alloys,J. Phys. F:Met. Phys., 1985, 15: 1911.
Hoyer, W., Jodicke, R., Short-range and medium-range order in liquid Au-Ge alloys,J. Noncryst. Solids, 1995, 192/193: 102.
Homutova, E. V., Sluhovskii, O. I., Romanova, A. V., Structure of aluminum-iron melts, I.Phys. (Ukraine), 1986, 31(7): 1045.
Black, P. J., Cundall, J. A., The structure of aluminum-iron alloys,Acta Cryst., 1966, 20: 417.
Mondolfo, L. F.,Aluminum alloys: Structure and properties, London: Butterwortha, 1976, 244.
Wasada, Y.,Thc Structure of Noncrystalline Materials, New York: McGraw-Hill, 1980, 27–36.
Mckamey, C. G., DeVan, J. H., Tortorelli, P. F.et al, A review of recent developments in Fe3Al-based alloys,J. Mater. Res., 1991, 6(8): 1779.
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Qin, J., Bian, X., Wang, W. et al. Pre-peak on the structure factor of liquid hypoeutectic Al-Fe alloy. Chin.Sci.Bull. 43, 1219–1224 (1998). https://doi.org/10.1007/BF02883229
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DOI: https://doi.org/10.1007/BF02883229