Non-metallic Inclusions in Lamellar Graphite Iron

Abstract

Cast iron melts with two different carbon contents were used in this experiment. Quenched chill coins were extracted directly from the melting furnace and the size, the number and the composition of the non-metallic inclusions was examined using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and an automate inclusions analysis system (EDAX). Large number of non-metallic inclusions was found in the chilled samples. Most of these inclusions are compounds of MnS with other elements. The number of the detected inclusions was found to increase with decreasing quenching temperature, while the number of large inclusions increases with the increase of the quenching temperature. This work provides supplementary data that helps a better understanding of the dependency between solidification rates, carbon composition, eutectic cells size, and constitutional undercooling in lamellar graphite iron.