A facile route for graded conversion of carbon fabric to silicon carbide fabric and its oxidation kinetics study in atmospheric high-temperature environment

Abstract

Silicon carbide fabric converted from carbon fabric was prepared by a facile halide-activated pack cementation method. The XRD, SEM and EDS analyses confirm the formation of SiC fibres with graded conversion of carbon to SiC from surface to core of individual carbon fibres of carbon fabric. The graded conversion of carbon fibre to SiC was uniform and homogeneous throughout the fabric dimension. The thermokinetics of oxidation in atmospheric environment was studied by TGA analysis. The reaction kinetics and governing mechanism for oxidation of bare carbon fabric and silicon carbide fabric were calculated using Kissinger and Ozawa methods. It was observed that the activation energy for bare carbon fabric and silicon carbide fabric converted from carbon fabric are 62 and 174 kJ mol-1, respectively. Further, it was observed that the silicon carbide fabric converted from carbon fabric follows the second-order surface reaction oxidation mechanism.