Effects of carbon black and graphene oxide additions on properties of ordinary portland cement composite

Abstract

The effect of the carbon black (CB) and graphene oxide (GO) on the mechanical properties and microstructure of cement mortar composite were studied by preparing CB-cement composite (CBCC) and GO-cement composite (GOCC) mortars. These properties were investigated by treating the cement mortar with 0.01% to 0.1% of GO and 0.1% to 1.0% of CB of the cement weight. The results revealed that the highest compressive strength obtained for 0.4% of CBCC and for 0.04% of GOCC. The incorporation of CB and GO to the cement motor simultaneously increased the compressive strength of the samples drastically. The highest increase of the compressive strength was equal to 43.27% for specimens evaluated at the age of 2 days for the cement composite specimens of 0.4% CB and 0.03% of GO. The addition of 0.4% of CB increased the flexural strength of cement motor up to 53.54% and 0.03% of GO increased the flexural strength of cement motor up to 46.54% for 28 days. The addition of the combination of 0.3% CB and 0.04% GO to the cement composite enhanced the flexural strength by 60.61%. GO was found to be able to accelerate the hydration process by forming the flower-like cement hydration crystals which contribute to the enhancement of the early mechanical properties. The analysis of the microstructure relieved that the addition of CB provides the filling effect while GO could affect the growth form of cement hydration products.