AES与计算机模拟技术研究Ce-P晶界共偏聚

Study of Ce-P Cosegregation on Grain Boundaries by AES and Computer Modelling

用俄歇能谱分析(AES),结合计算机模拟技术研究稀土元素Ce与杂质元素P在铁中的晶界共偏聚规律。实验结果表明,在P含量较低的情况下,Ce有抑制P晶界偏聚的作用,而当P含量较高时,Ce却有促进P晶界偏聚的作用。计算机模拟结果表明,当晶界上P的偏聚量不同时,Ce原子与P原子在晶界形成的偏聚结构不同。Ce对P在晶界偏聚作用的改变主要是因为晶界偏聚的P浓度不同使Ce与P晶界共偏聚所形成的最低能量结构改变。

The Ce and P cosegregation on the grain boundaries in a-iron was studied by Auger Electron Syectroscopy (AES) and computer modelling method. The result shows that in case of low P content in the alloys (P< 0.07wt%), Ce reduces the grain boundary segregation of P, but in the high P alloys (P>0.10wt%), Ce enhances the segregation of P. The computer modelling of this phenomenon indicates that the segregation structure of Ce and P on the grain boundary varies with the change of P content on the boundary. The main reason of the change of the interaction between Ce and P on the grain boundary is that the lowest energy structure of Ce-P cosegregation varies.