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本文研究了Al67Mn8Ti24Nb1复相金属间化合物在高能球磨过程中的亚稳态转变及亚稳粉末在加热时重有序化．由L12结构的基体和由DO22型Al3（Ti，Nb）第二相组成的Al67MN8Ti24Nb1复相合金在球磨过程中，L12相有序度下降、DO22相溶入，经15h后合金呈化学无序的fcc过饱和固溶体，继续球磨则逐步转变成非晶态，其亚稳转变过程中的结构演变顺序为：Ll2十DO22→Ll2（弱有序）→无序fcc→fcc＋非晶→非晶．利用100／200和110／220二对衍射峰计算有序应，虽然变化趋势相同，但两者下降速率不同，按110／220这一对衍射峰计算的有序度下降更快，表明合金在球磨过程中会造成结构上的异向性；非晶态合金加热时发生重有序化，其结构转变序列为：非晶态→无序fcc→弱有序Ll2并开始析出DO22相→完全有序Ll2并充分析出第二相．
In this paper, the metastable transition of Al67Mn8Ti24Nb1 complex phase intermetallics during high energy ball milling and the reordering of metastable powders upon heating were investigated. In the ball milling process, the order of the L12 phase decreased and the DO22 phase dissolved into the Al67MN8Ti24Nb1 complex phase composed of the L12 structure and the second phase of DO22-type Al3 (Ti, Nb) phase. After 15h, the alloy was chemically disordered fcc supersaturated solid solution, and then continue to gradually change into a ball milling amorphous state, its metastable transformation process of structural evolution sequence: Ll2 ten DO22 → Ll2 (weak order) → disordered fcc → fcc + amorphous → amorphous. Using 100/200 and 110/220 two pairs of diffraction peaks to calculate the order, although the same trend, but the rate of decline of the two, according to 110/220 of the diffraction peak calculated order degree faster, indicating that the alloy in Ball milling process will cause structural anisotropy; amorphous alloy reheat heating occurs when the sequence of its structural transformation: amorphous → chaotic fcc → weak order Ll2 and began to precipitate DO22 phase → completely Sequence Ll2 and fully precipitate the second phase.