Abstract
Flake graphite cast iron using steel can scraps (SCS) as raw materials was melted in a high frequency induction furnace and cast into several kinds of molds to examine chilling tendency, tensile strength, Brinell hardness, microstructure and chemical composition. EPMA analysis and X-ray microdiffraction were carried out to determine the distribution of Al.
The Al, Ti, Cr, Sn, Zn, and Mg contents increased while the P and S contents decreased with increasing amount of SCS compounded flake graphite cast iron. About 6.46 % of the Al content remained in the specimen when the SCS compounding rate was 100 %.
The chill depth decreased with increasing amount of SCS compounded and increased when more than 40 % was compounded. The tensile strength increased with the amount of SCS compounded and markedly decreased when more than 20 % was compounded. Brinell hardness increased slightly with increasing amount of SCS compounded and markedly increased when more than 40 % was compounded. The graphite structure changed from type A graphite to dendritic in the specimen with more than 40 % of SCS compounded.
By EPMA analysis, the Al-rich phase with high contents of Al and C was observed in granular type pearlite which formed in the specimen with more than 40 % of SCS compounded. X-ray diffraction patterns corresponding to Al-Fe-C ternary compounds (AlFe3C0.5) were obtained in this phase. The chilling tendency and mechanical properties of the specimen with less than 20 % of SCS compounded was similar to that without SCS.
