10 July 2008
10 July 2008
The University of Bristol and Imperial College London have won a £1.2M four-year research award from EPSRC and DSTL to develop methods to arrest, redirect and self-heal composite structures.
Currently, the 'no growth' approach (i.e. damage propagation from a defect constitutes failure) is the mindset of the composites industry, which has led to excessively heavy components, shackling of innovative design, and a need for frequent inspection during service. The aim of CRASHCOMPS is to exploit understanding of compressive damage modes and predictive models, to facilitate a step change in composite design philosophy, such that damage growth can be tolerated. Uniquely, composites offer the freedom to 'tailor' internal architecture, hybridise and introduce novel features in order to achieve such a capability.
Firstly, crack arrest/redirection concepts in polymer composite structures under monotonic compressive loading will be formulated and demonstrated. These concepts will be designed to inhibit the growth of rapid, unstable cracks, such that global (catastrophic) failure of the structure is hindered. Secondly, these structures will incorporate a self-healing capability whereby the arrested crack will then be autonomously healed. This is analogous to the numerous examples in nature where materials are generally damage tolerant and capable of self-repair. To maximise the potential for success, a core theme combining new or near-term technologies for crack arrest and self-healing will be investigated and supplemented by additional exploratory topics offering radical new approaches such as CNT reinforcement, piezoelectric stiffening, shear thickening materials, tow steering and novel resin delivery systems for self healing. As and when these ideas mature and are proven advantageous, they will be merged into the core activities.
It is envisaged that the main beneficiaries of this research will be engineers within UK aerospace, marine and transport industries. It will offer potential solutions to significantly improve the damage tolerance of composite components. A free annual CRASHCOMP workshop will be held at University of Bristol and Imperial College London in alternate years, providing a forum for academics, researchers and industry to review the results and influence the direction of the programme.
CRASHCOMP is being run by Dr Ian Bond at the University of Bristol (Advanced Composites Centre for Innovation and Science) and Dr Emile Greenhalgh at Imperial College London (The Composites Centre).
Solvay has signed a ten-year agreement for the supply of composites and adhesives to be used across Bell's military and commercial rotorcraft programmes, including the Bell 429, 407, 505, 525, V-22, and UH-1.
SGL Carbon and Fraunhofer IGCV have officially opened the Fibre Placement Centre (FPC) at SGL's site in Meitingen, Germany. Compositence, BA Composites and the Chair for Carbon Composites at the Technical University of Munich have also joined the alliance, and Coriolis Group and Cevotec are planning to come on board as partners.
With the aim developing a broader platform for additive manufacturing (AM) technologies, the University of Exeter, UK, and Victrex, have formed a strategic partnership to introduce next-generation polyaryletherketone (PAEK) polymers and composites while improving the performance of the underlying AM processes.