Entropy-stabilized multi-component alloys have been considered to be prospective structural materials attributing to their impressive mechanical and functional properties. The local chemical complexions, microstates and configurational transformations are essential to reveal the structure–property relationship, thus, to promote the development of advanced multi-component alloys. In the present work, effects of local lattice distortion (LLD) and microstates of various configurations on the equilibrium volume (V₀), total energy, Fermi energy, magnetic moment (μ_Mag) and electron work function (Φ) and bonding structures of the Fe–Mn–Al medium entropy alloy (MEA) have been investigated comprehensively by first-principles calculations. It is found that the Φ and μ_Mag of those MEA are proportional to the V₀, which is dominated by lattice distortion. In terms of bonding charge density, both the strengthened clusters or the so-called short-range order structures and the weakly bonded spots or weak spots are characterized. While the presence of weakly bonded Al atoms implies a large LLD/mismatch, the Fe–Mn bonding pairs result in the formation of strengthened clusters, which dominate the local microstates and the configurational transitions. The variations of μ_Mag are associated with the enhancement of the nearest neighbor magnetic Fe and Mn atoms, attributing to the LLD caused by Al atoms, the local changes in the electronic structures. This work provides an atomic and electronic insight into the microstate-dominated solid-solution strengthening mechanism of Fe–Mn–Al MEA.

熵稳定的多组分合金因其令人印象深刻的机械和功能特性而被认为是有前景的结构材料。局部化学络合、微观状态和构型转变对于揭示结构-性能关系至关重要，从而促进先进多组分合金的发展。在目前的工作中，局部晶格畸变 (LLD) 和各种配置的微观状态对平衡体积 ( V ₀ )、总能量、费米能量、磁矩 ( μ _Mag ) 和电子功函数 ( Φ ) 的影响) 和 Fe-Mn-Al 中熵合金 (MEA) 的键合结构已经通过第一性原理计算得到了全面的研究。发现这些MEA的Φ和μ _Mag与V ₀成正比，V ₀由晶格畸变支配。在键合电荷密度方面，增强的团簇或所谓的短程有序结构和弱键合点或弱点都具有特征。虽然弱键合的 Al 原子的存在意味着大的 LLD/失配，但 Fe-Mn 键合对导致形成增强的团簇，这主导了局部微观状态和构型转变。μ _Mag的变化与最近邻磁性 Fe 和 Mn 原子的增强有关，归因于 Al 原子引起的 LLD，电子结构的局部变化。这项工作提供了对 Fe-Mn-Al MEA 微态主导的固溶强化机制的原子和电子学见解。