Project title: Modelling Damage in Environmental Barrier Coatings on Woven SiC/SiC composite substrates.
Supervisors: Dr Daniel Balint (Mech.Eng) and Prof. Ferri Aliabadi(Aeronautics)
The current jet engine industry is moving towards using more sustainable, efficient and environmentally friendly materials for different parts such as turbine blades, while maintaining the capabilities of the existing alloys. SiC/SiC woven composite is a strong candidate in this process because of its exceptional mechanical and high temperature properties. Using SiC in the form of a woven composite not only has the amazing properties of SiC but also it gives the option to strengthen the material in different directions by changing the angle of weaved fibres. The main advantage is the fact that as the material undergoes impact or high stress the micro-cracks between the fibres and the matrix will allow ductile deformation and energy dissipation, which allows them to survive the harsh environment. However it is susceptible to moisture and oxidation, for which environmental barrier coatings (EBC) have been introduced.
Understanding the damage mechanism and behaviour of environmental barrier coating on SiC/SiC woven is an important step towards enabling turbine engines to run hotter and have higher efficiencies. This idea forms the basis for my project, which was designed to use meshfree method as the main modelling method for this system because it can have more flexibility and higher accuracy than finite element for complex geometries such as woven composites.
The project goes across scales by connecting the material’s behaviour at the micro-scale to the macro- scale through homogenisation of what is known as a representative volume element (RVE), which is the smallest repeatable unit cell for a woven composite. The homogenisation of the RVE allows for modelling large scale components such as a turbine blade.