Abstract Solubility and diffusion of boron and oxygen in the γ -TiAl intermetallic compound are herein investigated by first-principle calculations. On the basis of the space group of the γ phase, the accommodation of the light atoms in the various interstitial positions is studied by density functional theory. Diffusion coefficients are also obtained from ab initio calculations. Barrier energies for the boron and oxygen diffusion among the different stable interstitial sites are computed using the Nudged Elastic Band method and atomic jumping rates are obtained from the Transitional State Theory. Diffusion coefficients are obtained from the solution of the transport equation in the infinite time limit, using the analytical Multi-State Diffusion method. The methodology here applied is validated by the good agreement between the computed diffusion coefficient of boron and the experimental data available in the literature for this species.

中文翻译：

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氧和硼在γ-TiAl中的溶解度和扩散的第一性原理研究

摘要 本文通过第一性原理计算研究了硼和氧在γ-TiAl金属间化合物中的溶解度和扩散。在γ相空间群的基础上，利用密度泛函理论研究了轻原子在各个间隙位置的调节。扩散系数也可从 ab initio 计算中获得。使用轻推弹性带方法计算硼和氧在不同稳定间隙位点之间扩散的势垒能量，并从过渡态理论获得原子跳跃率。扩散系数是从无限时限内的传输方程的解中获得的，使用解析多态扩散方法。