铸铁中Mn和Si偏析行为的研究

SEGREGATION OF Mn AND Si IN GREY CAST IRON

通过逐层抛磨,结合着色腐蚀法获得铸铁中共晶团及卵形枝晶横向最大二维切面,应用电子探针研究了其中Mn和Si的偏析分布与含量的关系。结果表明:在凝固速度不变时,Mn和Si在其中的实际分配系数K,偏析系数Ks不随其含量而变化;而Mn和Si的偏析梯度K_R却随其含量的变化而变化。

An optimal two--dimensional transverse section of eutectic cells or ellipsoid austenite dendrites in the grey cast iron specimen was prepared by polishing layer by layer to- gether with etching and coloring. The segregation of Mn and Si with relation to their contents in the grey cast iron was examined by EMPA. The actual partition and segregation coefficients of Mn and Si in the grey cast iron were found to be not varied with their contents, but their segre-gation gradient to be different to various contents of them.