Alumina-Carbon Refractory Castables Containing Calcium-Aluminate Coatings on Graphite

R. Halder, S. Moitra, H. Acharjee, A. Chakraborty, S. Mukhopadhyay

Department of Chemical Technology,Ceramic Engin. Division, University of Calcutta/Kolkata – 700009/India


Volume 8, Issue 4, Pages 79 - 84


The physical properties namely bulk density, apparent porosity, cold crushing strength of carbon-containing high alumina based refractory castable containing both natural and modified graphites (94 % fixed carbon) have been evaluated within the temperature region 110–1500 °C. The densification behaviour of graphite-free and graphite-containing castable matrices has been characterized too by their thermal and thermomechanical characteristics up to 1500 °C. The role of coated graphite on improved performance of the refractory ceramics was explored by thermogravimetry, X-ray diffraction, microstructure and thermal shock resistance studies. It is suggested that the hydrophilic thin film containing calcium aluminate phases encouraged graphite retention in castable matrix.


graphite, calcium aluminate, refractory castable


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