灰铸铁电渣重熔过程石墨球化现象的研究

实验证明，采用高Ｓｉ含量铸铁自耗电极和含稀土氧化物的ＣａＦ２基熔渣，在直流反极性电渣重熔条件下，可制得球墨铸铁，铸铁中石墨球化现象是铁水经电化学变质处理的结果，熔渣中Ｍｇ１Ｃｅ阳离子在渣－金界面阴极区被还原进入铁水熔池，起到球化剂的作用，提高阳极区自耗电极中的Ｓｉ含量，可以抑制渣中Ｆｅ阳离子的形成，有助于上述电池化学还原反应的进行，这对建立新的冶金工艺技术有一定意义。

GRAPHITE NODULAR PHENOMENA DURING THE ESR OF CAST IRON

Based on the principles of the electrochemical modifying treatment for molten cast iron, preparing ductile iron in ESR process tinder D.C. condition without adding spheroidizing inoculant alloys has been studied in laboratory. The key operation of ESR for producing ductile iron is to increase the silicon content of consumable grey iron electrode and use CaF2-based slags containing rare-earth chide or alkaline-earth oxide and magenisium fluoride. Under the condition of D.C. reversed polarity, the anodic corrosion reaction silicon at the consumable electrode tip leads to a decrease of ferrous oxide concentrationin molten slag, therefore, the cathodic reduction of magnesium canon or cerium cation at the interface between slag and metal pool happens easily.A small amout of nodulizing element such as Mg and Ce, being transferred from slag into metal pool make graphite spheroidizing in remelted ingot. This new method of producing ductile iron in ESR process seems to be useful for the development of new metallurgical technology.