利用时间相关的微观相场法模拟弹性应变作用下 Ni75 Alx V25-x 合金 Ni3 Al 和 Ni3 V 共格沉淀取向排列组织演化，明晰应变能对取向排列组织形貌的影响，追踪 Ni3 Al 和 Ni3 V 沉淀相形核、长大过程的原子占位解析取向排列的微观原子特征。计算结果表明：应变能阻碍形核，改变沉淀相 Ni3 Al 和 Ni3 V 的析出序列，诱发原子取向扩散形成取向排列组织；取向排列组织受温度和合金成分影响，低温下2相取向不明显，温度较高时，取向排列倾向加强。Al 成分较低时，取向排列明显；Al 成分增加，取向排列倾向弱化。原子占位的时间演化曲线定量表征了沉淀相析出全过程 Ni、Al、V 3种组元在有序沉淀相 Ni3 Al 和 Ni3 V 的亚晶格位置的占位随时间演化，应变能推迟了 Ni3 Al 相 VNi、NiAl、VAl 原子占位达到平衡的时间，但对 NiNi 和 AlNi 的占位达到平衡的时间并无大的影响。应变能抑制了 Ni3 V 相反位缺陷 VNiⅡ、NiV 和第3组元占位 AlNiⅠ、AlNiⅡ、AlV ，诱发了反位缺陷 VNiⅠ。%A time dependent microscopic phase field model was applied to simulate the temporal evolution of directional arrange-ment microstructures caused by coherent Ni3 Al and Ni3 V precipitates in Ni75 Alx V25-x alloy upon the action of elastic strain energy. The influence of elastic strain energy on the directional arrangement microstructures and morphology was illustrated,and their atomic characteristics were demonstrated by tracing the atomic site occupancies during the nucleation and growth process of Ni3 Al and Ni3 V precipitates.The computational results indicate that the elastic strain energy hinders nucleation,changes the precipitate sequence of Ni3 Al and Ni3 V phase,and induces the directional diffusion of components forming directional arrangement micro-structure,which shows temperature and composition correlation.The directional arrangement is not evident at relatively low tem-perature or high Al content;however,atelevated temperature or low Al content,the directional arrangement becomes obvious. The temporal evolution of atomic site occupancy with time quantitatively characterizes the evolution of site occupancy for Ni,Al, and V components at the sublattices of both Ni3 Al and Ni3 V phases during the whole precipitation process.For Ni3 Al phase,the elastic strain energy impedes the atomic site occupancy of VNi ,NiAl ,VAl ,but has little effect on NiNi and AlNi .For Ni3 V phase, the elastic strain energy restrains the antisite defect of VNiI ,Niv and ternary alloying element AlNiI ,AlNiI ,Alv,but induces an-tisite defect VNiI .
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