氢脆会导致暴露在含H环境中的金属变脆并开裂，对能源、制造、运输和航空航天等行业构成严重风险，理解H与钢的相互作用在控制氢脆问题中起着至关重要的作用。本工作利用基于密度泛函理论的第一性原理方法，计算了不同合金元素对H原子溶入完整的及有空位缺陷的α-Fe基固溶体的影响，并根据晶体轨道Hamilton布居分析了H原子与合金元素、Fe原子的相互作用，并用爬坡图像弹性带(CI-NEB)方法计算了合金元素对H原子在α-Fe基固溶体中扩散的影响。结果表明，H原子均倾向溶于合金原子的第二、第三近邻四面体间隙，且溶解焓取决于H与最近邻的合金原子或Fe原子之间的键强；有空位缺陷时，H原子在合金化后Sc、V、Cr、Mn、Co、Ni、Cu的第一近邻空位处的溶解焓比在完整固溶体的四面体间隙位的溶解焓低，而固溶Al、Si、Ti、Zr、Nb、Eu、W的效果则相反；Ti、Cu、Zr、Nb及稀土元素的固溶会增加H原子从合金原子的次近邻至第三近邻四面体间隙的扩散能垒，同时降低其反方向的能垒，而固溶Si、V、Cr、Mn、Co、Ni、Mo、W的效果则相反。

Hydrogen embrittlement causes metals exposed to H-containing environments to become brittle and crack, posing serious risks to industries such as energy, manufacturing, transportation, and aerospace. Understanding the interaction between hydrogen and steel is crucial for addressing hydrogen embrittlement challenges. This study uses first-principles methods based on the density functional theory to examine how different alloying elements influence the dissolution of H atoms in α-Fe-based solid solutions, both with and without vacancy defects. The interactions between H atoms and alloying elements, as well as Fe atoms are analyzed using crystal orbital Hamilton populations. Additionally, the climbing image-nudged elastic band (CI-NEB) method was used to calculate the influence of the alloying elements on the diffusion of H atoms in α-Fe-based solid solutions. The results indicate that H atoms preferentially dissolve in the second and third nearest tetrahedral interstitial sites of alloy atoms. The solution enthalpy of H atoms is determined by the bond strength between the H atom and the nearest alloy atom as well as Fe atoms. For systems with vacancy defects after alloying, the solution enthalpies of H atoms at the first nearest vacancy for elements, such as Sc, V, Cr, Mn, Co, Ni, and Cu are lower than those at the tetrahedral interstitial sites of the complete α-Fe-based solid solutions. However, the opposite effect is observed for systems containing Al, Si, Ti, Zr, Nb, Eu, and W. Furthermore, alloying with Ti, Cu, Zr, Nb, and rare-earth elements increases the diffusion energy barriers for H atoms moving from the second nearest tetrahedral interstitial site to the third nearest site, while reducing diffusion energy barriers in the opposite direction. Conversely, the opposite effects are observed in α-Fe-based solid solutions containing Si, V, Cr, Mn, Co, Ni, Mo, and W.