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将Al、Pb粉末按照Al 2 2 5Pb(at% ,下同 )的配比进行了机械合金化 ,并对Al Pb合金的物相、晶粒尺寸、点阵常数作了测定和分析。结果表明 ,机械合金化可以获得Al Pb纳米晶超饱和固溶体。参照Miedema半经验理论模型 ,计算了该合金系的相变驱动力 ,分析指出当Pb含量为 86 8%～ 98 4 %时 ,该合金系存在发生非晶的化学驱动力。利用机械合金化动力学机制分析了Al Pb形成过饱和固溶体和非晶的可能性 ,其中Al 2 2 5Pb形成固溶体的自由能要低于形成非晶的自由能 ,但都大于零
The Al and Pb powders were mechanically alloyed according to the ratio of Al 2 2 5Pb (at%, the same below), and the phase, grain size and lattice constant of Al Pb alloy were measured and analyzed. The results show that the mechanical alloying of Al Pb nanocrystalline supersaturated solid solution. Based on Miedema semi-empirical model, the driving force of phase transformation was calculated. It is pointed out that the chemical driving force of amorphous alloy exists when the Pb content is 86.8% ~ 98.4%. The mechanical alloying kinetics mechanism was used to analyze the possibility of supersaturated solid solutions and amorphous forms of Al Pb, in which the free energy of Al 2 25Pb solid solution is lower than the free energy of forming amorphous,