Anomalous Graphite in Magnesium Cast Iron Castings - 2..

The conditions of formation of anomalous graphite at the thermal nodes of massive castings of cast iron containing spheroidal graphite are considered. The active (specific) surface of growth of vermicular graphite is much greater than that of spheroidal graphite in cast iron with the same bulk content of free carbon. The appearance of anomalous structures at the thermal nodes of magnesium cast iron castings is caused by a change in the bulk crystallization rate in time and by an attenuation, during solidification of the modifying action of the graphitizing additives introduced into the melt.