高温条件促进晶粒长大，导致晶粒抗位错性能削弱，机械性能降低。因此，深入了解Fe-Cr-Al合金的高温蠕变行为对于Fe-Cr-Al合金在高温下的应用至关重要。分子动力学模拟作为重要的研究工具为纳米级金属和合金的蠕变行为及其潜在机理提供了全新的见解，而这些数据单纯依靠实验手段尚无法获取。蠕变变形机制由应力因子与晶粒因子初步判定，通过晶体微观结构演化特征进一步证实。研究表明，温度与应力对合金蠕变速率影响较大，晶粒尺寸和合金组分影响较小。蠕变速率随Cr和Al含量的增加而增加，但随晶粒尺寸增加，蠕变速率有所降低。随着应力升高，蠕变机制由晶界扩散转变为晶界滑移，最终以位错运动为主导。应力转折点分别为0.8 GPa和1.8 GPa。随着温度升高，位错运动机制由黏性滑移转变为攀移运动。在本研究范围内，晶粒尺寸与合金成分对FeCrAl合金蠕变机制影响较小。

High temperature conditions promote grain growth, resulting in grain dislocation resistance and mechanical properties. Therefore, a thorough understanding of the high-temperature creep behavior of Fe-Cr-Al alloys is very important for the application of Fe-Cr-Al alloys at high temperatures. As an important research tool, molecular dynamics simulation provides new insights into the creep behavior and underlying mechanism of nanoscale metals and alloys, but these data cannot be obtained by experimental means alone. The creep deformation mechanism is preliminarily determined by stress factor and grain factor and further confirmed by the evolution characteristics of crystal microstructure. The results show that temperature and stress have great influence on creep rate of alloy, while grain size and alloy composition have little influence. The creep rate increases with the increase of Cr and Al content, but decreases with the increase of grain size. With the increase of stress, the creep mechanism changes from grain boundary diffusion to grain boundary slip, and finally the dislocation motion is dominant. The stress turning points are 0.8 GPa and 1.8 GPa, respectively. With the increase of temperature, the dislocation motion mechanism changes from viscous slip to climbing motion. In the scope of this study, the effect of grain size and alloy composition on the creep mechanism of FeCrAl alloy is small.