Fe-P、Fe-Mn-P、Fe-Cr-P系合金晶界偏聚的穆斯堡尔谱学研究

STUDY ON GRAIN BOUNDARY SEGREGATION IN Fe-P, Fe-Mn-P and Fe-Cr-P ALLOYS BY MOSSBAUER TECHNIQUE

本文通过穆斯堡尔谱技术并结合作者过去应用俄歇谱议和力学手段所得到的实验结果对Fe-P、Fe-Mn-P、Fe-Cr-P系合金的晶界偏聚和电子相互作用进行了研究。研究表明,由于Mn、Cr及P元素向晶界偏聚,造成了晶界Fe原子近邻环境的改变,从而使Fe(3d)电子与近邻中(3p)及(3d)电子产生了交互作用,这种交互作用是改变晶界强度的一个重要因素,M(M=Mn,Cr) (3d)电子与P(3p)电子之间存在交互作用,因此,M与P共偏聚的作用结果并不是它们单独作用结果的简单相加。由于穆斯堡尔技术对电、磁相互作用的高度敏感特性,因此,该技术必将成为晶界偏聚及晶界脆性研究中的重要手段。

The grain boundary segregation and electronic interactions at grain boundary region of Fe-P, Fe-Mn-P and Fe-Cr-P alloys are studied by Mossbauer technique and some other experiments. The results show that, because Mn, Cr and P segregate to grain boundaries, the neighboring arrangement around Fe atoms at grain boundaries is altered. The electronic interactions between Fe(3d) electrons and the neighboring (3p) and (3d) electrons are discussed in detail, which are thought to have a great influence on the grain boundary strength. The 3d electrons of Mn and Cr also have interactions with 3p electrons of P; therefore, the co-segregation of Mn-P or Cr-P is not the simple combination of the segregation of Mn and P or Cr and P. The results in this paper also shows that the Mossbauer technique, since it is extremely sensitive to electric and magnetic interactions, will be of great importance in studying grain boundary segregation and tempering embrittlement.