A high improvement of tensile properties and interfacial interaction of calcium silicate hydrate/hexagonal boron nitride layered nanostructures via defect field

Abstract

Previous studies have shown that the increase in Young's modulus of cement-based materials by h-BN (about 20%) is lower than that of graphene and graphene oxide (an increase of 35.8%−78.6%). In order to further improve the interfacial interaction between calcium silicate hydrate (CSH) and hBN nanostructures, a series of defective hBN nanostructures were inserted between CSH layers to form defective hBN-CSH layered nanostructures. The interfacial interaction and tensile properties of hBN-CSH layered nanostructures were investigated, in considering the effect of internal (defect sizes in hBN) and external field (strain rate and temperature). The results show that the failure strain and stress of CSH models are enhanced by 18.18% and 14.74% with the incorporation of pure hBN while an increase of 35.53% and 31.58% in failure strain and stress is achieved by incorporating defective hBN (R3), attributed to high interfacial interaction. In addition, the tensile strain of defective hBN-CSH nanostructures (with a decrease of 33.49%) is more sensitive to temperature than that of free-defect hBN-CSH (with a decrease of 29.71%). Also, the tensile strain of defective hBN-CSH (R3) nanostructure (with an increase of 6.49%) is more sensitive to strain rate than that of free-defect hBN-CSH (with an increase of 4.38%). By constructing different interface interactions, a parameterized scheme is provided for the optimization and regulation of the spatial structure of the cement matrix.