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

Electrolytic extraction-radiometry and microradioautography techniques 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 increases,the concentration of Ce in graphite tends to saturate,relatively large amount of Ce dissolves in the alloy.Usually,the sulphur also concentrates 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 nodular when Ce was saturated and,as vermicular while it was semi-saturated.

电沉积Ni—Ce—S非晶态合金

研究了镀液组成和工艺条件对Ｎｉ—Ｃｅ—Ｓ非晶态合金沉积层的影响，结果表明，镀层中的Ｓ含量随电流密度、镀液的ｐＨ值和硫代硫酸钠浓度的变化而变化，但与镀液中的氯化钾浓度无关；Ｘ射线衍射图说明，当镀层中的Ｓ含量超过３０％时，镀层为非晶态结构；扫描电子显微镜表明，当镀层中Ｓ含量增加时，镀层的微裂纹减少且变细，当镀层中Ｃｅ含量增加时，晶粒会细化。