INITIAL MELTING FOR MANUFACTURING CGI CASTIRON AND METHOD FOR MANUFACTURING NON-INOCULATING TYPE CGI CASTIRON USING THE SAME

摘要

Initial molten metal for manufacturing CGI cast iron and a method for manufacturing non-inoculation type CGI cast iron using the same are disclosed. A method for manufacturing non-inoculation type CGI cast iron according to the present invention includes the following steps of: preparing initial molten metal consisting of 3.5 to 3.7 wt% of carbon (C), 1.4 to 1.6 wt% of silicon (Si), 0.3 to 0.5 wt% of manganese (Mn), 0.15 to 0.25 wt% of phosphorus (P), 0.2 to 0.4 wt% of sulfur (S), 1.35 to 1.45 wt% of copper (Cu), 0.015 to 0.025 wt% of boron (B), remainder iron (Fe), and other inevitable impurities; adding 1.0 to 1.5 parts by weight of graphite spheroidizing agent including silicon (Si) and magnesium (Mg) per 100 parts by weight of the initial molten metal; and casting and cooling the initial molten metal to which the graphite spheroidizing agent is added. [Reference numerals] (AA) Start;(BB) End;(S110) Preparing initial molten metal;(S120) Adding a spheroidizing agent;(S130) Casting and cooling