Ce,S在高纯Fe-C-Si合金中的分布及其对石墨形态的影响

本文采用电解分离-放射性测量法及显微自射线照相法研究了Ce及S在高纯Fe-C-Si合金各相中的分布和其对石墨形态的影响。实验结果表明:Ce除了与S,O形成夹杂外,首先在石墨中富集;随着合金中Ce含量的增加,石墨中Ce量趋于饱和,大量的Ce以合金化形式存在于铸铁之中;S也在石墨中富集,如合金中S含量继续增加,则以FeS形式存在于共晶团边界;合金中固溶S量极微;石墨形态与Ce在石墨中的吸附和镶嵌程度有关,呈饱和镶嵌吸附时,石墨程球状;呈半饱和态时,石墨为蠕虫状。

DISTRIBUTION OF Ce AND S IN Fe-C-Si ALLOY AND THEIR INFLUENCE ON MORPHOLOGY OF GRAPHITE

Electrolytic extraction-radiometry and microradioautography tech- niques were used to study the distribution of nodulizing element Ce and anti- nodulizing element S in phases of high purity Fe-C-Si alloy. The results show that, besides forming inclusions, most of Ce atoms concentrate in graphite firstly. As the Ce content increase, the concentration of Ce in graphite tends to saturate, relati- vely large amount of Ce dissolves in the alloy. Usually, the sulphur also concen- trates in graphite, however, it may exist in the form of FeS at the eutectic colony boundaries, if the concentration of S is at a quite high level. Very little amount of S dissolves in the alloy. The morphology of graphite depends upon the degree of saturation of Ce. It appears as nodula when Ce was saturated, and as vermicular while it was semi-saturated.