NODULAR GRAPHITE CAST IRON, ITS HEAT TREATMENT AND CONNECTING PARTS MADE OF NODULAR GRAPHITE CAST IRON

摘要

PURPOSE:To enhance the corrosion resistance and mechanical properties of nodular graphite cast iron by adding prescribed amounts of C, Si, Mn, S, P, Cu, Ni, etc. to the cast iron and forming a ferrite structure. CONSTITUTION:To nodular graphite cast iron are added 2.5-3.8% C, 2-3.5% Si, =0.4% Mn, =0.02% S, =0.1% P, 0.3-1% CU, =1% Ni and 0.08% one or more among Mg, Ca, Ce and Y. This graphite cast iron is heated to the austenitizing temp. to form an austenite structure, and by slowly cooling the iron, the structure is converted into a ferrite structure. Thus, the corrosion resistance and mechanical properties are enhanced.