Effect of graphene oxide nanosheets of microstructure and mechanical properties of cement composites

We investigate the performance of graphene oxide (GO) in improving mechanical properties of cement composites. A polycarboxylate superplasticizer was used to improve the dispersion of GO flakes in the cement. The mechanical strength of graphene-cement nanocomposites containing 0.1–2 wt% GO and 0.5 wt% superplasticizer was measured and compared with that of cement prepared without GO. We found that the tensile strength of the cement mortar increased with GO content, reaching 1.5%, a 48% increase in tensile strength. Ultra high-resolution field emission scanning electron microscopy (FE-SEM) used to observe the fracture surface of samples containing 1.5 wt% GO indicated that the nano-GO flakes were well dispersed in the matrix, and no aggregates were observed. FE-SEM observation also revealed good bonding between the GO surfaces and the surrounding cement matrix. In addition, XRD diffraction data showed growth of the calcium silicate hydrates (C-S-H) gels in GO cement mortar compared with the normal cement mortar.

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Effects of temperature on microstructure and mechanical properties of IN718 reinforced by reduced graphene oxide through spark plasma sintering

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.07.071 ◽

2018 ◽

Vol 767 ◽

pp. 675-681 ◽

Cited By ~ 20

Author(s):

Shuan Ma ◽

Yanjie Yang ◽

Ang Li ◽

Shiqi Zhou ◽

Lan Shi ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Spark Plasma Sintering ◽

Microstructure And Mechanical Properties ◽

Plasma Sintering ◽

Reduced Graphene ◽

Spark Plasma ◽

Effects Of Temperature

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Effect of Graphene Oxide on Mechanical Properties of Cement Mortar and its Strengthening Mechanism

Materials ◽

10.3390/ma12223753 ◽

2019 ◽

Vol 12 (22) ◽

pp. 3753 ◽

Cited By ~ 7

Author(s):

Yahui Wang ◽

Jiawen Yang ◽

Dong Ouyang

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Cement Hydration ◽

Strengthening Mechanism ◽

Cement Composites ◽

Working Mechanism ◽

Cement Pastes ◽

Cement Mortars ◽

Binder Ratio ◽

Growth Space

The effects of the water–binder ratio and different graphene oxide (GO) sizes on the mechanical properties of GO-cement composites were systematically studied by preparing GO-cement mortars. The scanning electron microscopy observation (SEM) of the surface and fracture surface of cement pastes was carried out to study the morphology of cement hydration crystals in GO-cement systems under different space conditions. It was found that GO nanosheets significantly improved the compressive, flexural, and tensile strengths of cement mortars. When the dosage of GO nanosheets was 0.03% by weight of cement, the compressive, flexural, and tensile strengths at 28 days increased by 21.37%, 39.62%, and 53.77%, respectively, but GO was not found to be able to regulate the formation of flower-like cement hydration crystals. It was only shown that the growth space had an important influence on the morphology of hydrates. A possible working mechanism was proposed by which GO nanosheets prevented the expansion of microcracks in the cement pastes via a shield effect, thus enhancing the strength and toughness of the cement composites.

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