抄録
Microstructures and mechanical properties of flake and spheroidal graphite cast irons having various thicknesses were correlated to the average cooling rate υ numerically calculated. Both the average diameter of graphite in spheroidal graphite iron and the average diameter of eutectic cell in flake graphite iron are functions of υn, where n is −0.24 and −0.25 respectively. The area ratio of pearlite to matrix depends on the average cooling rate υ. Both the hardness (HRB) and tensile properties of spheroidal graphite iron depend on the area ratio of pearlite phase to matrix, while those of flake graphite iron depend on both the eutectic cell diameter and area ratio of pearlite to matrix.
