Three-dimensional hybrid composites for repair and recycling PhD

High-performance composites are increasingly used in a range of endurance critical applications where maintenance and repair opportunities are limited and costly e.g., autonomous vehicles and offshore wind turbines. Operational wear and tear and isolated damage events, like impact, can resulting in significant losses in material performance. Furthermore, at end-of-life, it is often difficult to separate out the components to allow for recycling.  

This project simultaneously addresses the challenges of autonomous repairability and end-of-life recyclability by using through-thickness reinforcement to embed large-diameter (>1 mm) metallic hybridising elements into composite laminates. These novel through-thickness elements will be used as a means of targeted heat introduction to activate re-processible polymer matrices including thermoplastic or vitrimer-based resins. This intrinsic self-healing negates the need for external heating apparatus like hot presses or ovens to melt the composite’s matrix. The academic knowledge gap exists in understanding the thermo-mechanical interaction between metallic TT-elements and composite constituents which is foundational and necessary for exploiting this technology for repair and recycling purposes.

The Composites and Advanced Materials Centre at Cranfield University has world-class facilities to support through-thickness reinforcement activity and functional/mechanical characterisation of materials including an electrical, thermal, and thermo-mechanical characterisation suite, pilot scale composites manufacturing equipment including a tufting robot, and z-pinning gantry as well as the mechanical testing lab in the School of Aerospace, Transport and Manufacturing. This project supports a Royal Academy of Engineering Research Fellowship project entitled Multifunctional z-direction hybridisation of composites (web link: https://www.cranfield.ac.uk/research-projects/multifunctional-z-direction-hybridisation-of-composites).

The activities in this project will cover manufacturing process development and manufacture of hybridised components, optimisation of material parameters through finite-element simulation, testing and validation of functionality and performance. This will represent an industrial paradigm shift in the use of through-thickness reinforcement in composites, expanding this potential to recycling and repair. Increased longevity and durability of the structures associated with the solution will affect a savings on maintenance, repair, and replacement. 

This work will involve collaboration with the Royal Academy of Engineering Research Fellowship project partners including Prof Michele Meo at the University of Southampton (UoS), Laser Additive Solutions (LAS), and the National Composites Centre (NCC). The candidate will be expected to engage with these collaborators as well as participate in knowledge exchange through a series of visits to project partners for manufacturing and testing trials, with a high level of interaction expected with the University of Southampton. The candidate will be expected and encouraged to participate in at least two industry crucial conferences including the International Conference on Composite Materials. 

This role will develop practical composites manufacturing and process/performance simulation skills with a particular emphasis on through-thickness reinforcement which is currently an area of skills development that is in high-demand across the UK composite’s base. The candidate will be encouraged to engage with the in-house or external training activities for research and transferrable skills and there is an is an expectation that the PhD candidate will assist in the mentoring of MSc students which will endow useful people management and learning support skills.