In-situ tensile tests under SEM and X-ray computed micro-tomography aimed at studying a self-healing matrix composite submitted to different thermomechanical cycles

Abstract

Composites made of Ceramic for both fibres and matrix are three dimensional (3D) structured materials aimed at being used in aerospace applications. Material is submitted to mechanical stresses at high temperatures in oxidizing and corrosive environments for long durations. During thermomechanical cycles, damage, oxidation and healing-phenomenon appear and develop in the material. X-Ray Computed Micro-Tomography (μCT) and tensile test under Scanning Electron Microscopy (SEM) are solutions which allow an experimental study of these phenomenons. These techniques are performed for the study of the behaviour of the oxide (solid or liquid) in the crack of the material. The influence of the state of the oxide in the crack was analysed during tensile test under SEM or μCT. The observation of the crack shape allows to determine the influence of the oxide on the reclosure of the crack during the unloading.