Oxidation kinetics and mechanisms of four-direction carbon/carbon composites and their components in carbon dioxide at high temperature

Thermogravimetric analysis and scanning electron microscopy were used to study the oxidation kinetics of four-direction carbon/carbon composites and their components (fibres and matrix) in a CO₂ atmosphere at high temperature. The ablation processes were restricted to reaction-limited oxidation. The mass loss rate was estimated for the four-direction carbon/carbon composites and their components within the temperature of range of 600-1400 °C. The pressure exponent for the reaction of carbon/carbon composites and CO₂ was 0.62, and the pre-exponential factor and activation energy for the reactions of CO₂ and the carbon/carbon composites, carbon fibres and matrix were determined, respectively.