Solid combustion synthesis of β SiC powders

A method of obtainment of β SiC powders under conditions of the self-propagating high-temperature synthesis (SHS), based on the exothermic reaction between silicon micropowders and active carbon substrates (carbon black and charcoal), has been developed. The method described in the paper is characterised by a low ignition temperature (1250–1300°C) and a short duration of synthesis (3–5 minutes). The product retains the morphology of the carbon substrates used what indicates the occurrence of a mechanism similar to the one suggested in the case of carbon fibres-silicon systems, namely the occurrence of alternating steps of solution of carbon in liquid silicon and crystallisation of SiC from supersaturated solution.