Effect of CaCO₃ nanoparticles on the microstructure and fracture toughness of ceramic nanocomposites

Abstract

This study investigated the effect of using calcium carbonate (CaCO 3) nanoparticles on the microstructural properties, flexural strength and fracture toughness of ceramic nanomaterials. The flexural strength and fracture toughness were evaluated for CaCO 3 nanoparticle contents of 1%, 2%, and 3% by weight of cement powder. The microstructural analyses from X-ray diffraction showed that nano-CaCO 3 improved the microstructure of nanocomposites because it reduces the tricalcium silicate and dicalcium silicate peaks and increases the calcium silicate hydrate products. Moreover, the results showed that the nanocomposites with 1 wt% nano-CaCO 3 exhibited the maximum flexural strength and fracture toughness compared to the other composites owing to the filler and nucleation effect of nano-CaCO 3. In addition, nano-CaCO 3 could resist the unstable micro-crack propagation in cement nanocomposites by filling the micro-cracks and voids. Future applications in synthesis or steel fiber-reinforced concrete or ceramic nanocomposites could benefit from the use of the analyses presented in this study.

Influence of pozzolanic addition on strength and microstructure of metakaolin-based concrete

“…Fig 9 illustrates the periodic change in the interaction between CH and NS or MS at the interface, as determined by the XRD pattern analysis. In addition to expediting the cement hydration process, the pozzolanic material also undergoes a reaction with CH [ 85 ]. The investigation of the CH consumption within a matrix comprising NS or MS can be effectively demonstrated through the analysis of intensity fluctuations observed in the primary diffraction peaks of crystals at specific 2θ values [ 86 ].…”

“…These findings reconfirm that the pozzolanic activity of NS is greater than that of MS in the initial phases [ 49 ]. According to these findings, NS exhibits a considerably greater number of nucleation sites for hydration products than MS during the initial stages [ 85 ]. Hence, the inclusion of NS in the matrix has been observed to enhance the mechanical strength, particularly during the early stages of development, leading to better resistance to deteriorating environments, as studied in the sulfate attack and water penetration analyses.…”

Resisting spread of environmental-pollution diseases due to Portland-cement industries: green nanoclay applications

“…Special storage conditions are needed to avoid deterioration of mechanical properties due to temperature change and humidity [12][13][14][15][16][17] . Some researchers have tried to enhance the properties of conventional Portland-cement [36][37][38][39][40] by directly adding clay to Portland-cement. However, the present aim is different because previous researchers do not solve the problems of Portland-cement, but they encourage the use of Portland-cement and potable water.…”

“…In this study, we develop a new application of nanoclay-based polymer nanocomposites [18][19][20][21][22][23][24][25][26][27][28][29][30][42][43][44] as green nanocomposite cements to replace Portland-cement for concrete and construction industries. As a result of the study, changes between conventional Portland-cement concrete and recent green CPNC-concrete conclude main differences; the main important results are avoiding a large ratio of environmental pollution during the production and application of Portland-cement [31][32][33][34][36][37][38][39][40] , avoiding diseases caused by cement dust and preventing use of drinking water for the concrete construction industry, especially for countries with few water resources. Moreover, these results can minimize construction time and prevent steel corrosion due to the absence of water use.…”

“…This solution will use green natural materials that do not cause pollution, it will use polymers that are inexpensive, and it may use recycled polymers to prevent millions of tons of polymers from entering the environment every year. Developed CPNC-concrete and construction materials have many other advantages in comparison to Portland-cement-based materials [31][32][33][34][36][37][38][39][40] , like ductility, avoiding sudden brittle failure and crushing, saving water-consumption, eliminating use of Portland-cement, eco-friendliness, and new applications.…”