根据电子衍射多束动力学原理 ,分别计算了与入射电子束方向相关的γ相TiAl中Ti和Al位置的沿 [1 0 0 ]、[1 1 0 ]和 [0 1 1 ]的快电子概率密度 .在计算中考虑了吸收效应 .计算和实验结果显示了在不同的晶带轴 ,或同一晶带轴的不同方向 ,电子通道效应有很大的差别 .因此在用轴电子通道统计法测定杂质原子占位的实验中 ,必须选择合适的晶带轴和电子束入射方向 .在实验前先进行模拟计算是一个可取的方法 . According to the principle of electron beam diffraction multi-beam dynamics, the fast electron probabilities along [1 0 0], [1 1 0] and [0 1 1] of the Ti and Al positions in the γ-phase TiAl related to the incident electron beam direction were calculated respectively Density. The absorption effect is taken into account in the calculations. The calculation and experimental results show that the electron channel effects differ greatly in different directions of the ribbon axis or in the same ribbon axis. Therefore, In the experiment of impurity atom occupying, it is necessary to select the appropriate belt axis and the incident direction of the electron beam. It is a preferable method to perform simulation before experiment.