Predictive modelling and experimental measurement of composite forming behaviour

Wang, Jinhuo (2008) Predictive modelling and experimental measurement of composite forming behaviour. PhD thesis, University of Nottingham.

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Abstract

Optimised design of textile composite structures based on computer simulation techniques requires an understanding of the deformation behaviour during forming of 3-dimensional double-curvature components. Purely predictive material models are highly desirable to facilitate an optimised design scheme and to significantly reduce time and cost at the design stage, such as experimental characterisation. In-plane shear and out-of-plane bending are usually thought to be the key forming mechanisms. Therefore, this thesis is concerned with studies of the shear and bending behaviour by experimental characterisation and theoretical modelling.

Micromechanical interaction between fibre and matrix offers fundamental understanding of deformation mechanisms at the micro-scale level, leading to development of composite viscosity models, as input to shear and bending models. The composite viscosity models were developed based on rheological behaviour during movement of fibres, and validation was performed using experimental results collected from the literature. A novel characterisation method for measuring the bending behaviour, by means of a large-displacement buckling test, was attempted due to some significant advantages over other methods. Development of a bending model was also undertaken for unidirectional composites but experimental validation suggests further study may be required for woven composites. The shear behaviour was characterised using a picture frame test for viscous polymer composites. To obtain reliable experimental data, some efforts of improving the characterisation method were made. The experimental results were then used to validate a shear model, suggesting that further improvement is required, in terms of weave patterns, rate and temperature dependence.

Item Type:Thesis (PhD)
Supervisors:Long, A.C.
Clifford, M.J.
Uncontrolled Keywords:Composite forming, deformation mechanism, bending behaviour, shear behaviour, composite shear viscosity
Faculties/Schools:UK Campuses > Faculty of Engineering > School of Mechanical, Materials and Manufacturing Engineering
ID Code:602
Deposited By:Jinhuo Wang
Deposited On:26 Jan 2009
Last Modified:23 Mar 2009 11:10

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