Investigations into the influence of micro-to-nanoscale porosity on carbon fibre composite coupon strength

Project: UK industry

Project Details


Composite materials are increasingly being used to improve the efficiency of aircraft, wind turbines and other lightweight structures. Certification of these materials is based upon an exhaustive testing program of large numbers of small coupons. One of the main issues with this approach is the presence and proximity of ‘free edges’ in these small specimens, which typically leads to conservative estimates of coupon strength when compared to bulk values. As a result, we are underusing the incredible capabilities of these materials – so what can we do?

One factors which is known to influence edge effects is micro-to-nanoscale porosity. In particular, it is important to better characterise and understand the size and distribution of these features at interfaces where stresses are concentrated. Therefore, in this study we will assess the impact of different sample preparation techniques on the presence of voids and the strength of coupons. This will allow us to produce more representative specimens, and ultimately make the most of structural composites – to allow us to fly further, produce more energy and drive faster!

This project is of real practical importance and will be supported by GKN Aerospace. It will allow the student to explore a range of different techniques and disciplines; from plasma surface treatment, to small-scale mechanical testing and data processing. Characterisation will be performed using microscale computational tomography and scanning electron microscopy – some state-of-the-art techniques!
Short titleFull PhD studentship
Effective start/end date25/02/1920/07/20