抄録
Recently, cerium-containing pig iron has been produced for the purpose of making spheroidal graphite cast iron. Cerium has a high boiling point, low vapor pressure and large solubility in iron. From these characteristics of cerium, it is expected that ductile cast iron can be produced by just remelting this iron without adding any graphite spheroidizers. But this iron has some typical properties, that is, it has a strong tendency to chill and is sensitive to the cooling rate, casting thickness and inoculations. In order to obtain good spheroidal graphite in this iron, it is necessary to soldify at a fast cooling rate after the optimum addition of the most suitable inoculants. Also, the cementite which have precipitated are easily decomposed by graphitization treatment within a short time. Cerium-containing pig iron seems to be a raw material in which the structure can be easily controlled by maintaining strict casting conditions.
