Crystallization Behaviour of some Steelmaking Slags

The present study was aimed at highlighting the final properties of two different steelmaking slags which undergo different cooling rates. The experiments were conducted in laboratory scale using an induction furnace. One of the slags originates from an electric arc furnace (EAF) (high-alloyed) and the second slag from a basic oxygen furnace (BOF). The treatment of the slag included re-melting along with different cooling rates. The material collected from the tests was characterized through X-ray diffraction, scanning electron microscopy as well as thermodynamic calculations which were compared with experimental results, for confirmation. The results indicate that both the EAF and BOF slags show increased reactivity with water, as well as a decrease in crystal size when rapid cooling is applied. The wustite-type solid solution (Mg,Fe,Mn)O varies in composition depending on the cooling conditions. Metastable Ca3SiO5 was found in the rapidly- cooled BOF slag.