【摘要】 本实验使用光学显微镜和分析电镜检查了石墨形态。实验结果表明，在含稀土的球铁中加入铋，锑可以使石墨球数量显著增加，并使石墨球更加细小、圆整，消除了大断面球铁中的畸变石墨。另外，检查结果发现，石墨核心主要是由稀土与铋、锑、铝等元素组成的复杂化合物。因此，可以认为导致大断面球铁石墨畸变的根本原因是缺乏足够的稳定结晶核心。更多还原

【Abstract】 The graphite morphology is examined by microscope and the analytical electron microscope,The experimental results indicate that trace elements Bi and Sb added to the ductile iron containing rare earth may make increase of nodule amount remarkably,nodules become smaller and rounder,the degenerated graphite in heavy-section ductile iron is eliminated.It is also found that this graphite nucleus mainly consists of some complex componds being composed of RE,Bi, Sb,Al etc.Therefore,it is considered that principal reason causing degenerated graphite in heavy-section ductile iron is lacking stable graphite nucleus.更多还原