Effect of Low Oxidation Graphene Oxide on Physical and Mechanical Properties of MCC Type Refractory Castable

The present work investigates medium cement content (MCC) refractory castable modified by graphene oxide (GO) having oxidation degree of ~ 4. For the evaluation of the effect of GO on the hydration and structure of the castable, XRD and SEM analyses were performed. The study also included heating-cooling cycles and mechanical tests. The addition of GO changes the hydration of calcium aluminate cement (CAC) and the structure of CAC stone: the maximum intensities corresponding to the more stable hydrates of C₂AH₈ were found to be higher and those of unstable CAH₁₀, presumably lower, presumably, when the MCC samples are fired at 1000 ℃ temperature, a larger amount of anorthite mineral is formed, improving the mechanical properties of MCC. After curing and drying at 110 ℃, the addition of GO does not affect density and strength, but after the samples are treated at 1000 ℃, the strength of the MCC samples increases by ~ 9% compared to the control samples. The residual compressive strength after 30 heating-cooling cycles also increases ~30% compared to the control samples.