Manufacturing method of cast iron alloy and cast iron of high toughness and ostempered graphite cast iron using the same

摘要

TECHNICAL FIELD The present invention relates to a cast iron alloy and a method for producing high-strength cast iron and ostempered spheroidal graphite iron using the cast iron alloy.;According to the present invention, there is provided a ferritic stainless steel comprising 3.2 to 3.7 wt% of C, 2.0 to 2.5 wt% of Si, 0.1 to 0.4 wt% of Mn, 0.01 to 0.07 wt% of P, 0.001 to 0.02 wt% of S, 0.02 to 0.05 wt% 0.4% by weight of Cu, 0.6 to 1.2% by weight of Cu, or 1.2 to 2.0% by weight of Ni and the balance of Fe and unavoidable impurities. The spheroidization ratio is 80%²Of ferrite, 8 to 30% of ferrite and 70 to 92% of pearlite, and a heat treatment method therefor.