【摘要】 采用第一性原理计算方法研究了TD3合金中O相、B2相和α₂相的合金原子空位形成能及氧原子在三相中的能量稳定性和扩散行为。计算结果表明：三相中的Al原子空位形成能均低于Ti和Nb，有利于TD3合金表面生成α-Al₂O₃占主导地位的氧化膜。氧原子在O相、B2相和α₂相的八面体间隙位置的间隙能低于四面体间隙位置处，且在富钛八面体间隙位置的间隙能最低，最低氧原子间隙能分别为–5.0815、–4.9425和–5.9315 e V。氧原子在O相、B2相和α₂相沿最佳扩散路径扩散需要跨越的势垒分别为0.812、1.913和1.164 e V。更多还原

【Abstract】 The first-principles calculation method was used to study the alloy atom vacancy formation energies of O phase,B2 phase andα₂ phase in TD3 alloy,and the energy stability and diffusion behavior of oxygen atoms in the three phases.The calculation results show that the vacancy formation energies of Al atoms in the three phases are all lower than those of Ti and Nb,which is beneficial to the formation of α-Al₂O₃ dominated oxide film on the surface of TD3 alloy.The interstitial energies of oxygen atoms in the octahedral interstitial positions of O phase,B2 phase and α₂ phase are lower than those of tetrahedral interstitial positions,and the interstitial energy of titanium-rich octahedral interstitial positions is the lowest,the lowest oxygen atom interstitial energies are–5.0815,–4.9425 and–5.9315 e V,respectively.The barriers to be crossed for oxygen atoms to diffuse along the best diffusion path in O phase,B2 phase and α₂phase are 0.812,1.913 and 1.164 e V,respectively.更多还原