Impact of Nano-Cr2O3 Addition on the Properties of Aluminous Cements Containing Spinel

Abstract

In this paper, the effect of nano-Cr₂O₃ addition on the properties of aluminous cement containing MgAl₂O₄ spinel was investigated. For this reason, the raw dolomite was used as raw material along with calcined alumina for the preparation of the aluminous cement. Then, the compositions containing different amounts of nano-Cr₂O₃ particles were fired at   1450 °C and their mineralogical compositions and microstructures were investigated. The setting times of prepared cements were measured after grounding and ball-milling. Besides, the slag resistance of refractory castables containing prepared cements was evaluated. The results showed that nano-Cr₂O₃ addition has effect on the increasing of spinel and CA₂ and decreasing of CA and C₁₂A₇ phases in the cement composition. The decreasing of C₁₂A₇ leads to increasing of setting times of cement. Besides, the slag resistance of refractory castables containing prepared cements is improved due to increasing of spinel and decreasing of C₁₂A₇ amount in the cement composition.

DOI: http://dx.doi.org/10.5755/j01.ms.21.1.5211