PhD thesis

Polymer Matrix Composite (PMC) materials are more and more employed for the realization of Aircraft Structural parts, leading to consistent weight saving and CO 2 emission reduction. These materials are progressively integrated into “warm temperature” parts, such as the first compression fan blade stages of aero-engines. In these parts, under harsh environmental conditions, thermo-oxidation ageing takes place, due to oxygen diffusion/reaction within the polymer matrix molecular network at high temperature. This phenomenon is strictly related to the external environmental conditions (temperature, oxygen partial pressure, …) and leads to material degradation, erosion, embrittlement and premature failure. Thermo-oxidation of PMC has been extensively studied by performing “laboratory” ageing tests in climatic chamber/oven setup, reproducing “artificially” the external environmental conditions but without reproducing the true aero-thermal environment encountered by aero-engine fan blade structures. The new challenge is to characterize thermo-oxidative ageing under realistic environments, including aero-thermal effects.