C/C composite oxidation model II. Oxidation experimental investigations

In order to characterize C/C composites during consumption and to document a carbon-carbon oxidation model, specific oxidation experimental facilities were developed. Two different devices of a BLOx (Bench Laser for Oxidation ) feature were designed according to the atmosphere (molecular air, oxygen, water vapor). These facilities enable high-temperature material characteri zation to be performed in a well-defined atmosphere with independent contro l of temperature, pressure and gas flow conditions. Experiments carried out in these apparatuses lead to calculation of specific values of apparent ac tivation energies for reactions between different carbons and gases. The co herence between these activation energy values and the morphological charac terizations presented in the first part of this study was checked. Moreover a modular injection device allows us to conduct protection of carbon/carbo n composites by injecting some neutral gas at the back side of the sample. These apparatuses provide a large number of experimental results enabling u s to assess the oxidation model. (C) 1999 Elsevier Science Ltd. All rights reserved.