Crystal Structure and Hydration Characteristics of Tricalcium Silicate Doped with Magnesium Oxide

Abstract:

The research investigates various methods to identify magnesium oxide influences on the crystal structure and hydration properties of tricalcium silicate. The f-CaO content of the clinkers were analyzed by chemical analysis. The complex disordered superstructure of the tricalcium silicate has been studied by a joint XRD, NMR and TEM. The results show that MgO exerts a remarkable influence on the polymorphisms of C₃S. Mg is not only substitutional atom but also interstitial atom in the crystal lattice of tricalcium silicate. The HRTEM pattern of C₃S doped with MgO is covered by the various irregular lattice. The addition of appropriate amount of MgO in raw meal can change the formation kinetic of C₃S, slightly perturb the environment of SiO₄^4- tetrahedral, modify the crystal structure of C₃S and affect the hydration activity. Doped with MgO in the raw meal can slow down the hydration rate of alite slightly in early stage.

• Periodical: Advanced Materials Research (Volume 936)
• Pages: 1336-1341
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.936.1336
• Online since: June 2014
• Authors: Lin Chen*, Xu Wang, Xiao Dong Shen, Su Hua Ma, Wei Qiang Zhou
• Keywords: Hydration, MgO, Structure, Tricalcium Silicate

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