PREPARATION METHOD OF HIGH STRENGTH FLAKE GRAPHITE IRON AND FLAKE GRAPHITE IRON PREPARAED BY THE SAME METHOD AND ENGINE BODY FOR INTERNAL COMBUSTION ENGINE COMPRISING THE SAME

摘要

The present invention relates to a cast iron graphite cast iron having high strength, excellent workability and fluidity, a method for producing the cast iron graphite cast iron, and an engine body for an internal combustion engine including the cast iron graphite cast iron. More particularly, A small amount of strontium is added to cast iron containing silicon (Si), manganese (Mn), sulfur (S), phosphorus (P) and molybdenum (Mo) By controlling the ratio (S / Sr) with respect to the content and the content of strontium (Sr), the main composition is improved, the probability of occurrence of chill due to ferroalloy is low, the engine cylinder having stable tensile strength and yield strength, And to a method of manufacturing a piece-shaped graphite cast iron for a block and a head.