ASSCAST METAL OF PEARLITIC SPHEROIDAL GRAPHITE CAST IRON

摘要

PURPOSE:To omit the heat treatment, and to obtain the titled cast metal stably keeping the pearlite percentage above 80%, by restricting the amount of C, Si, Mn, and residual Mg, and by controlling the amount of Cu in respect of diameter of the cast metal. CONSTITUTION:The as-cast metal of the pearlitic spheroidal graphite cast iron is obtained with the composition as follows; 3.3%=C=3.6%, 2.1%=Si=2.6%, 0.5%=Mn=1.0%, 0.03%= residual Mg=0.06%, (0.002D+0.1)%=Cu=2.0%, in which D means the diameter or equivalent wall thickness of the cast metal, and the balance Fe. In the diagram, the pearlite percentage above 80% can be obtained in the left upper region above the line B; this straight line B is formulated in respect of the diameter Dmmphi of the cast metal and the amount of Cu, as Cu%= 0.002XD+0.05. USE:The crank shaft of the farm engine or the automobile engine and the cylinder cover of the Diesel engine.