Published online by Cambridge University Press: 21 February 2011
Synthetic and commercial Fe-C-Si irons have been frozen under controlled conditions after vacuum purification in order to correlate graphite forms with freezing conditions and alloy composition. It was found that graphite morphology was influenced prirmarily by the sulphur and oxygen contents and the rate of cooling. The various modes of graphite growth are discussed, particularly the appearance of the coral and compacted graphite surfaces at high magnification after the addition of oxygen or nitrogen.