Manganese substitutions into the portland cement clinker phases

Abstract

The effect of manganese substitution into the crystal structures of the main Portland cement clinker phases (3CaO.SiO₂, 2CaO.SiO₂, 3CaO.Al₂O₃, 2CaO.Fe₂O₃ y 4CaO.Al₂O₃.Fe₂O₃) has been studied by X-ray and analytical electron microscopy. In oxidizing conditions, the limit of solid solution in 3CaO.SiO₂ is about 0.72 ±0.11% (wt), while in 2CaO.SiO₂ is 1.53±0,12%(wt). Mn solid solubility on 3CaO.Al₂O₃structure, in oxidizing conditions is close to 0.78 ± 0,12% (wt). In identical atmosphere, the proportion of Mn in the ferrite phases (2CaO.Fe₂O₃ and 4CaO.Al₂O₃.Fe₂O₃) is 6.80 ± 0.87% (wt) and 6.7% (wt), respectively. To each mentioned clinker phases a solid solution formula has been proposed. In these formula, the manganese substitutions and also the different oxidation states which this element can be introduced in those crystalline structure are defined.