High performance titanium alloys are being increasingly used in advanced airframes, particularly where elevated temperatures are experienced (e.g. in close proximity to engines). While highly corrosion and oxidation resistant, titanium alloys are prone to degradation caused by oxygen diffusion into the surface which in extreme cases can lead to a change in microstructure by oxygen stabilising the alpha phase and embrittlement. The interaction between surface oxygen embrittlement and fatigue crack initiation is currently poorly understood, which makes predicting the endurance of components in service very difficult. It is therefore important to obtain a clearer in-depth understanding of the synergistic interactions between elevated temperature fatigue and an oxidising environment.

The main aim of the Project is to develop a systematic fundamental understanding of the synergistic interactions between elevated temperature fatigue and an oxidising environment on the mechanisms of fatigue crack initiation.

The Project is supervised through the Advanced Metallic Research Programme (AMRP) within Airbus Airframe R&T.