Development of ceramic based on steel slag with different magnesium content

Abstract

The steel slag based ceramics (SSBC) with different contents of magnesium ions were prepared by conventional sintering process. The variations of linear shrinkage, water absorption, bulk density and apparent porosity of the samples fired at different temperatures from 1130 to 1210°C were measured. The phase formation and microstructure of final ceramics were observed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicate that increasing magnesium ions content in SSBC does not change the crystal phases but increases the sintering temperature. The final phases in SSBC are pyroxenes including augite and diopside. Crystalline phases in SSBC form before densification. Substitution of Fe²⁺ for Mg²⁺ in phases would increase amount of Fe²⁺ in crystal, but decreases the amount in liquid, which is the main factor of the sintering temperature increase. Good degrees of densification and high crystallinity of ceramics show good mechanical properties.