The Characterization of Steel Slag by Alkali Activation

摘要

This paper presents a characterization analysis of alkali-activated steel slag. The effect ratio of steel slag and ferronickel slag which are the precursor materials on the compressive strength of the alkali-activated materials was investigated. The combination of sodium hydroxide solution of 15 moles concentration and sodium silicate was used as an alkaline activator. The ratio between steel slag and alkaline liquid was fixed at 3.31 for all mixtures. Ambient curing (20℃ - 25℃) are used throughout the experiment. Compressive strength shows the alkali-activated steel slag presented high strength at 14 days curing which is 21. 56 MPa. In comparison, the alkali activated steel slag had better strength than 50/50 Fe/SS alkali-activated slag which only achieved 16.75 MPa. Result obtained shows that alkali-activated steel slag had better water absorption than 50/50 Fe/SS alkali-activated slag at 7 days curing. Furthermore, the activation of steel slag was contributed to the presences of gehlenite, larnite, akermanite and magnetite. Lastly, the alkali-activated steel slag presents the vibration of the Si-O bonds at wave number 970.46 cm ﹣1) contributed by the calcium silicate hydrate.