SPATIALLY RESOLVED ELASTIC MODULUS OF MAGNESIUM SILICATE HYDRATE: A CEMENTITIOUS MATERIAL

Abstract

Magnesium-based cements such as magnesium silicate hydrate (MSH) have drawn interest as an environmentally friendly substitute for ordinary Portland cement because of their potential for reduced carbon footprint. The precise determination of these materials' elastic moduli is important to better assess their mechanical performance. Atomic force microscopy (AFM) is an effective tool for precise and spatially resolved quantification of nanomechanical characteristics of materials, including thin films. In this study, elastic modulus maps of MSH grown on single crystal mica surfaces were obtained using amplitude modulation-frequency modulation AFM. The effects of the Mg:Si ratio and morphology on the elastic modulus of MSH overgrowths were investigated. Using mica as a reference material, the results reveal elastic moduli ranging from 5 to 15 GPa and 40 to 64 GPa, depending on the growth reaction time and overgrowth morphology. The findings of this study demonstrate the effectiveness of AFM in describing the mechanical characteristics of cementitious phases and suggest that MSH-based materials have a significant potential for use in a variety of construction and building applications.