SPHEROIDAL GRAPHITE CAST IRON HAVING BAINITE MATRIX

摘要

PURPOSE:To improve the shock resistance of spheroidal graphite cast iron at low temp. by specifying the average grain size of graphite in the bainite matrix. CONSTITUTION:The average grain size of graphite in the bainite matrix of spheroidal graphite cast iron is regulated to <=20mum. The shock resistance of the cast iron at about -20--80 deg.C is improved, so a new use for the cast iron can be found. The grain size regulation is carried out by selecting the cooling rate of molten metal after pouring or a mold used.