Advanced mechanical characterisation of next generation inorganic fibre materials towards sustainable fibre manufacturing for energy & transport applications

This project sits in the area of materials design for ultralightweight sustainable fibre materials and advanced characterisation of their mechanical properties. Customised ceramic fibres offer excellent properties for high-temperature performance and thermal insulation applications. They are crucial for applications in extreme environments. To uncover their full potential research is needed to develop a better understanding of sustainable and cost-effective manufacturing methods of ceramic fibres with complex chemical compositions. Comprehensive studies of long-term fibre performance to assess their durability and degradation mechanisms in various environments are crucial to ensure their robustness and safe use in the long term. Therefore, developing reliable recipes alongside a fundamental understanding of how the precursor chemistry in conjunction with manufacturing processes affect the compositional and mechanical performance of next generation ceramic fibres is critical.  For example, by tuning the precursor chemistry, the Grobert Group has shown how 3-dimensional electrospun ceramic fibres with controlled porosity, typically produced in the form of thin densely packed 2D mats of limited porosity, can be created in situ by modulating the spinning solution. Using high-speed camera observations revealed the formation mechanism of these 3D fibre assemblies and showed that more viscous solutions render thicker fibers with enhanced mechanical stiffness as examined by finite element analysis.

Within the Department of Materials, the candidate will develop synthetic methods for electrospinning continuous ceramic fibre assemblies and establish protocols for their mechanical testing of the assemblies ultimately geared towards single fibre testing. The fibre materials will be analysed using state-of-the-art characterisation techniques.

The candidate will be co-supervised by our industry partner QinetiQ. QinetiQ has been developing UK sovereign supply of oxide and carbide ceramic fibres over the past 12 years including continuous and short/chopped varieties. They have developed a pilot manufacture capability including research into efficient fibre spinning and winding. They have also developed CMC systems containing bespoke manufactured fibres for purposes including piezoelectric energy harvesting, high temperature structural and space applications.

The figure shows a typical electrospinning set-up for producing 3D fibre assemblies and the correlation between precursor viscosity its conductivity and the resulting fibre morphology. Cross-sections of individual fibres reveal the different porosities obtained depending on the precursor and synthesis conditions.