| Al70Cu20Fe10 samples were prepared by mechanical alloying (MA). Microstructure of milled products at different stages of milling was characterized by X-ray diffraction (XRD) and X-ray absorption fine structures (XAFS). The method overcame the difficulties in analysis of highly disordered structures. The results indicate that Al and Cu form inter-metallic compound Al2Cu with body-centered tetragonal structure after milling for 10h, then a small amount of AlFe3 with cubic structure was formed. With increasing milling time, Al2Cu and AlFe3 gradually transform to P-Al(Cu, Fe) solid solution of cubic crystal structure. Milling up to 40h, the XRD pattern only consists of single P-phase and un-reacted Al, Fe element. Continued milling up to 50h leads to the evolution of the mixture of a-Fe crystalline and AK Cu amorphous. The nano-crystallite size is about 16.8nm after milling for 10h..Annealing can accelerate reaction and renovate lattice strain introduced by high-energy milling, and also it is essential for the formation of quasi-crystalline. The XRD patterns of the sample annealed at 500℃ show that 10h of milling is an important turning-point before which no quasi-crystalline is observed. But after annealing of 1 Oh milled sample, the fraction of quasi-crystal phase decrease with increasing time and there is almost no evidence of it after 50h of milling. The XRD pattern of the sample annealed at 700℃ show that at the turning-point of 10h, the sample is mainly composed of β and i-phase, while i-phase is observed to be dominant. However, after milling for 20h i- phase disappeared and P-phase is the single phase. The are more intense i-phase peaks at 700℃ than at 500℃, which indicates that the proper annealing temperature is an important factor for the quasi-phase formation.In spite of annealing is added, milling of Al70Cu20Fe10 system for a long time results in the formation of Al(Cu, Fe) inter-metallic compound, indicating that β-Al(Cu, Fe) solid solution is quite stable.
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