A Multi-Scale Approach of Degradation Mechanisms inside a SiC(f)/Si-B-C(m) Based Self-Healing Matrix Composite in a Dry Oxidizing Environment

Ceramic matrix composites are potential candidates to replace the nickel-based alloys in advanced aeronautic engines. The durability of a SiC(f)/PyC(i)/Si-B-C(m) with a sequenced self-healing matrix and Nicalon fibers was investigated at low temperature. To better understand the degradation mechanisms inside this composite, a multi-scale approach was chosen. Firstly, the oxidation behavior of Nicalon fibers and the B4C phase was studied under dry air at 550 A degrees C. The composite structure was then aged in similar oxidizing conditions. Correlation between the different systems led to an accurate description of the degradation mechanisms inside a composite material and to an evaluation of the efficiency of the self-healing process.