Abstract Samples taken from three commercial runs of nodular cast iron, obtained from the same base metal, same nodularizing alloy, but different inoculants were studied. The percentages by weight of inoculant and nodularizing alloy were, respectively, 1.0% and 1.3%. In this way the nucleation and the growth of graphite nodules were studied by microstructural analysis using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). In this way, we observed that the growth sequence of the graphite nodules was associated to the formation of complex silicates rich in aluminum, calcium and barium around the graphite cores, generating an interface favorable to the heterogeneous graphite solidification from these particles of size larger than critical radius. Therefore, the race 1 sample inoculated with FeSi75% presented the lowest amount of nodules/mm2 and, consequently, less elongation, since there is a direct relation between the elongation and the number of nodules/mm2.

中文翻译：

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球墨铸铁中石墨颗粒的形核和长大

摘要 对从相同母材、相同球化合金、但不同孕育剂的三个商业化球墨铸铁中取出的样品进行了研究。孕育剂和球化合金的重量百分比分别为1.0%和1.3%。通过这种方式，使用扫描电子显微镜 (SEM) 和能量色散 X 射线光谱 (EDS) 通过显微结构分析来研究石墨球的成核和生长。通过这种方式，我们观察到石墨瘤的生长顺序与石墨核周围富含铝、钙和钡的复合硅酸盐的形成有关，从而产生有利于这些尺寸大于临界半径。所以，