Nodular graphite cast iron containing calcium, rare earth metals and magnesium and amethod for producing it

摘要

A nodular graphite cast iron contains .Rare earth metals.0.01-0.12% .Mg.0.006-0.04% .Ca.0.002-0.025% in which R.E.=0.9-4 (Mg). The alloys are made by adding to the molten cast iron an addition agent consisting of R.E. fluoride, MgF3 and Ca-Si with or without small additions of CaF2, MgSi, FeSi, CaC2. The fluorides may be partially substituted by CaF2, NaF or KF and Ca-Si may be partially substituted by Mg-Si, Fe-Si, R.E.-Mg-Si or CaC2. The cast iron may be unalloyed or may contain one or more of Cu, Ni, Cr and Mo. The chlorides of R.E. and Mg may also be used instead of the fluorides.