采用原子探针层析技术研究了核反应堆压力容器模拟钢中AlN相/α-Fe基体、富Cu相/α-Fe基体和AlN相/富Cu相三种相界面处Ni、Mn、P和C原子的偏聚特征.压力容器模拟钢经890℃保温0.5 h水淬,然后在500℃进行了20 h的时效处理.分析结果表明:Ni、Mn、C和P原子在富Cu相/AlN相界面上不发生偏聚;而在AlN相/α-Fe基体和富Cu相/α-Fe基体两种相界面上都会发生偏聚,且偏聚特征无明显区别,都是Mn的偏聚倾向大于Ni,C的偏聚倾向大于P.
The segregation characteristics of Ni, Mn, P and C atoms at the phase boundaries of AlN/α-Fe matrix, Cu-rich precip-itate/α-Fe matrix and AlN/Cu-rich precipitate in reactor pressure vessel ( RPV ) model steel were investigated by atom probe tomo-graphy ( APT) . RPV model steel specimens were heat treated at 890℃ for 0.5 h followed by water quenching and aging at 500℃ for 20 h. The results demonstrate that Ni, Mn, C and P atoms do not segregate to the Cu-rich phase/AlN phase boundary, only segregate to the AlN/α-Fe and Cu-rich nanophase/α-Fe phase boundaries, and their segregation characteristics have no significant differences. It is also observed that Mn has a larger segregation tendency than Ni, and C has a larger than P at both different phase boundaries of Cu-rich nanophase/α-Fe and AlN/α-Fe.