Analytic expressions for the temperature-dependent diffusion coefficient of oxygen along two directions in the α₂-Ti₃Al alloy are obtained using Landman's method. The estimation of oxygen diffusion coefficient as well as pre-exponential factor and the activation energy are performed using migration barriers calculated by the first principle method within density functional theory. The phonon frequencies required for estimating the jump rate are determined at initial and saddle oxygen sites. The factors that determine the oxygen diffusion in the alloy are revealed. The influence of impurities on the oxygen diffusion in the α₂-Ti₃Al alloy is discussed. The method applied in this work is validated by good agreement between the calculated diffusion coefficient of oxygen and available experimental data and theoretical results obtained within statistical approach.

利用兰德曼方法得到了α ₂ -Ti ₃铝合金中氧沿两个方向随温度变化的扩散系数的解析表达式。使用通过密度泛函理论中的第一原理方法计算的迁移势垒来估计氧扩散系数以及指前因子和活化能。估计跳跃率所需的声子频率在初始和鞍状氧位点确定。揭示了决定合金中氧扩散的因素。α ₂ -Ti ₃中杂质对氧扩散的影响讨论了铝合金。在这项工作中应用的方法通过计算的氧气扩散系数与可用实验数据和统计方法中获得的理论结果之间的良好一致性得到验证。