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在１０２３～１３７３Ｋ的初始温度范围和０．０５～２６８．９１Ｋ／ｓ的冷速范围内，用俄歇剖层分析确定了含硼Ｎｉ_３Ａｌ合金中硼的非平衡晶界偏聚行为。基于由空位在晶界湮灭所产生的体系自由能下降驱动可动的溶质－空位复合体向晶界迁移、从而产生溶质非平衡晶界偏聚的模型，导出了定量描述非平衡偏聚行为的解析表达式。理论计算结果与硼非平衡偏聚的试验数据相符。通过模拟实测确定Ｎｉ_３Ａｌ－Ｂ合金中硼及硼－空位复合体的扩散系数分别为：Ｄ＝１×１０￣（－６）ｅｘｐ［－１．９６（ｅＶ）／ｋＴ］和Ｄ_（Ｐ（Ｂ））＝１×１０￣（－）４ｅｘｐ［－１．９６（ｅＶ）／ｋＴ］（ｍ￣２／ｓ）；硼－空位复合体的结合能为Ｅ_（ｂ（Ｂ）＝０．５ｅＶ。
In the initial temperature range of 1023 ~ 1373K and the cooling rate of 0.05 ~ 268.91K / s, the non-equilibrium grain boundary segregation behavior of boron in boron-containing Ni_3Al alloy was confirmed by Auger fracture analysis. Based on the decrease of the free energy of the system caused by the annihilation of the vacancy in the grain boundary, the movable solute-vacancy complex migrates to the grain boundary, resulting in a model of solute imbalanced grain boundary segregation. A quantitative description of the unbalanced segregation behavior is derived Analytical expression. The theoretical calculation results are consistent with the experimental data of boron non-equilibrium segregation. The diffusivities of boron and boron-vacancy complexes in Ni 3 Al-B alloys were determined by simulated measurements as follows: D = 1 × 10 -6 (exp [-1.96 (eV) / kT] and D P ) = 1 × 10 ~ (-) 4exp [-1.96 (eV) / kT] (m ~ 2 / s). The binding energy of the boron-vacancy complex is E_ (b) = 0.5eV.