This is the first investigation on the micromorphology and kinetics evolution of Cr-rich α′ precipitates under Cr composition, irradiation and dislocation with the three-dimensional phase-field simulation. The statistical results of volume fraction, particle number density, and average particle size under different Cr composition are consistent with the APT results. The particle density and volume fraction of α′ precipitates increase with the increase of Cr composition (>9 at.%), while the mean radius decreases. Fitting the free energy curve to analyze the driving force and resistance of α′ precipitates. It is found that α′ precipitates preferentially nucleate in the dislocation core region due to the drive of dislocation elastic energy, while the nucleation in the dislocation free region is driven by chemical free energy. Growth of α′ precipitates is driven by chemical free energy and interface energy. The particle size distribution of 3dpa shows that the particle size distribution of α′ precipitates becomes more uniform with the increase of dislocation density. The strengthening model calculated from the simulation results shows that the Cr component has a great influence on the strengthening, and the total strength increases slightly with the increase of dislocation density.

这是首次使用三维相场模拟研究富铬 α' 析出物在 Cr 成分、辐照和位错作用下的微观形态和动力学演变。不同Cr组成下体积分数、颗粒数密度、平均粒径的统计结果与APT结果一致。α'析出物的颗粒密度和体积分数随着Cr成分的增加（>9 at.%）而增加，而平均半径减小。拟合自由能曲线分析α′析出物的驱动力和阻力。发现α'析出物由于位错弹性能的驱动优先在位错核心区形核，而在无位错区的形核则由化学自由能驱动。α'沉淀物的生长是由化学自由能和界面能驱动的。3dpa的粒度分布表明，随着位错密度的增加，α'相析出物的粒度分布变得更加均匀。由模拟结果计算出的强化模型表明，Cr成分对强化影响较大，总强度随位错密度的增加而略有增加。