HEAT-RESISTANT SPHERICAL GRAPHITE CAST IRON, METHOD FOR PRODUCING SAME AND ENGINE EXHAUST SYSTEM COMPRISING SAME

摘要

A heat-resistant spherical graphite cast iron comprises 3.2-3.4 wt% of carbon (C), 4.3-4.8 wt% of silicone (Si), 0.2-0.3 wt% of manganese (Mn), 0.8-1.0 wt% of molybdenum (Mo), 0.4-0.6 wt% of vanadium (V), 0.2-0.4 wt% of chrome (Cr), 0.2-0.4 wt% of niobium (Nb), inevitable impurities, and the remainder being iron (Fe) on the basis of the total weight thereof. The heat resistant spherical graphite cast iron further comprises 0.0045-0.0075 wt% of barium (Ba) on the basis of the total weight thereof, and the content ratio (Cr/Ba) of the chrome (Cr) to the barium (Ba) may be in the range between 26 and 89. The heat-resistant spherical graphite cast iron may have improved high-temperature tensile strength.