论文部分内容阅读
通过俄歇微探针定点成分分析和X射线粉末照像方法 ,分别对稀土在初生Si颗粒和共晶组织两相中的存在和分布特点进行了研究。结果表明 :稀土变质剂使初生Si颗粒由开花状板片变成多面体颗粒状。产生这种变化的原因是与稀土吸附并阻碍Si相沿孪晶凹坑的生长有关 ;在Al Si合金中 ,微量稀土主要存在于Si相 ,在Si相中分布较均匀 ,未发现选择性吸附和明显的浓度偏聚 ;微量稀土变质剂没有明显的形成化合物 ,不形成Si相的异质核心。
The characteristics of the existence and distribution of rare earth in the two phases of primary Si particles and eutectic structure were studied respectively by the method of point component analysis of Auger microprobe and X-ray powder photography. The results showed that the rare earth modifier changed the primary Si particles from the flowering plate into polyhedral particles. The reason for this change is that rare earths adsorbed and hindered the growth of twinned pits along the Si phase. In Al-Si alloys, trace rare earths were mainly present in the Si phase and distributed uniformly in the Si phase. No selective adsorption and Obvious concentration of segregation; trace rare earth modifier did not significantly form compounds, do not form heterogeneous Si core phase.