Showing papers by "Paul Robinson published in 2015"
TL;DR: In this paper, the authors exploit composites with overlapped discontinuities at the ply level to create a significantly non-linear response, due to progressive interlaminar damage under tensile loading.
84 citations
TL;DR: In this paper, the authors present some evidence which suggests that with the correct hardware and operating procedure/methodology, consistent and high quality carbon-epoxy laminates can be produced, with the possibility of scaling up the process, as demonstrated by the micro and macro-scale mechanical test results.
Abstract: Microwave heating has several major advantages over conventional conductive heating when used to cure carbon–epoxy composites, especially in speed of processing. Despite this and many other well-known advantages, microwave heating of carbon–epoxy composites has not taken off in industry, or even academia, due to the problems associated with microwave energy distribution, arcing, tool design and (ultimately) part quality and consistency, thus leading to a large scepticism regarding the technique/technology for heating such type of materials. This paper presents some evidence which suggests that with the correct hardware and operating procedure/methodology, consistent and high quality carbon–epoxy laminates can be produced, with the possibility of scaling up the process, as demonstrated by the micro- and macro-scale mechanical test results. Additionally, the author proposes a methodology to practically measure the maximum microwave penetration depth of a carbon–epoxy composite material.
83 citations
Journal Article•
TL;DR: In this article, the authors present some evidence which suggests that with the correct hardware and operating procedure/methodology, consistent and high quality carbon-epoxy laminates can be produced, with the possibility of scaling up the process, as demonstrated by the micro and macro-scale mechanical test results.
61 citations
TL;DR: In this paper, an electro-thermal anti-icing/de-icing device for carbon fiber composite aerostructures is described, where the heating element is an electroconductive carbon-based textile (ECT) by Gorix.
Abstract: The preliminary evaluation is described of a new electro-thermal anti-icing/de-icing device for carbon fibre composite aerostructures. The heating element is an electro-conductive carbon-based textile (ECT) by Gorix. Electrical shorting between the structural carbon fibres and the ECT was mitigated by incorporating an insulating layer formed of glass fibre plies or a polymer film. A laboratory-based anti-icing and de-icing test program demonstrated that the film-insulated devices yielded better performance than the glssass fibre insulated ones. The heating capability after impact damage was maintained as long as the ECT fabric was not breached to the extent of causing electrical shorting. A modified structural scarf repair was shown to restore the heating capacity of a damaged specimen.
53 citations
TL;DR: In this article, the authors investigated the potential of interleaving to delay catastrophic translaminar failure in unidirectional Carbon Fibre Reinforced Polymers (CFRPs) under tensile load.
20 citations
24 Jul 2015
TL;DR: In this article, the HiPerDiF method was used to produce high-quality specimens with consistent fibre length, good alignment, controlled volume fraction and uniformly distributed fibres. But the results of the experiments were limited to validate the results as the required fibre length leads to difficulties in producing high quality specimens.
Abstract: Continuous fibre reinforced composites have high properties for structural applications but tend to fail in a brittle manner, unlike metals. However, when the fibre aspect ratio is less than the critical value and a high level of fibre alignment is obtained, discontinuous fibre composites could potentially achieve a ductile or pseudo-ductile tensile response caused by deformation and slippage at the fibre ends. A lot of modelling work on aligned discontinuous fibre composites shows nonlinear behaviour on the stressstrain curve with a limited reduction of modulus and strength. Despite the interesting results from analytical studies, there have been limited experimental results to validate the models as the required fibre length leads to difficulties in producing high-quality specimens with consistent fibre length, good alignment, controlled volume fraction and uniformly distributed fibres. In this paper, specimens with highly aligned discontinuous fibres and with fibre length close to the critical value, which can bring a brittle-ductile transition, are manufactured with the HiPerDiF method (High Performance Discontinuous Fibre method) and tested in tension. In particular, 1 and 3 mm carbon fibres are used to manufacture composite specimens with epoxy and polypropylene matrices. The analytical solutions are compared with experimental results.
12 citations