CRack Arrest and Self-Healing in COMPosite Structures (CRASHCOMPS)

Although composites are now widely utilised there has been a reticence from designers in using them in safety critical applications, principally because of their sensitivity to defects. Since relatively minor damage can significantly reduce performance, the 'no growth' approach (i.e. damage propagation from a defect constitutes failure) is now the mindset of the composites industry. This has led to excessively heavy components, shackling of innovative design, and a need for frequent inspection during service. However, the research community has made considerable steps in understanding damage modes and the development of robust failure models. A step change in composites technology could be achieved by adopting a philosophy in which some damage growth can be tolerated (i.e. be 'damage tolerant' or 'fail-safe); this would provide considerable weight and cost savings and offer designers greater freedom to formulate new designs. Furthermore, there are numerous applications in which a component is expected to tolerate significant damage growth yet still be fit for service; for example, collision damage to a transport vehicle. In such an application, severe damage is introduced whilst the structure is under significant load, and subsequently crack growth is highly likely; a no-growth criterion cannot be used, and damage propagation must be tolerated. An effective approach to achieve this is by employing CRack Arrest and Self-Healing COMPosite Structures (CRASHCOMPS). Uniquely, composites offer the freedom to 'tailor' internal architecture, hybridise and introduce novel features in order to achieve such a capability.