Nanocarbon containing Al2O3 - C continuous casting refractories: Effect of graphite content

Alumina-carbon refractories are broadly used in the continuous casting area in the production of steel, mainly in the devices used to control flow, because of their thermal and mechanical properties. Continuous casting refractories contain approximately 30% of residual carbon after coking to impart and improve certain refractory properties. But this leads to the threat of carbon pick up by the molten steel for high-quality steel production. In the present work, nanocarbon is used in combination with graphite to reduce the total carbon content. The changes in physical and mechanical properties like bulk density and strength with the phase and microstructural development were studied. The density and strength values are decreasing with increase in the amount of graphite in the composition. Formation of aluminum carbide in nanocarbon containing batches enhances the strength development. High surface area nanocarbon possess high reactivity than the graphite and helps in carbide phase formation and it can easily disperse in the gaps between coarse, medium and fine alumina particles, thereby reduces the porosity, and enhances density and strength development. (C) 2017 Elsevier B.V. All rights reserved.