Enhancement of the oxidation resistance of the interfacial area in C/C composites. Part III: the effect of oxidation in dry or wet air on mechanical properties of C/C composites with internal protections

Tensile tests were carried out on C/deposit/C composites (100 nm B–C, Si–B–C and Si–C deposits) both before and after oxidation tests at 600 °C under dry or wet air flow for a time of 500 min. The composite failure stresses do not show a decrease when compared to the failure stress of C/C composites. Mechanical properties of composites are affected by damages induced during the oxidation tests. The more important the mass loss, the lower the failure stress. Only a slight influence of oxidation damage at interfacial zones was observed because the yarns within the loading axes are not affected at the sample gage level by the oxidation that progresses mainly from the ends of the samples.