School of Mechanical, Industrial and Aeronautical Engineering

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Author: search.filters.author.Reid, R.G.Subject: search.filters.subject.Manufacturing process

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    Effects of processing conditions on the mechanical and water absorption properties of resin transfer moulded kenaf fibre reinforced polyester composite laminates.
    (Elsevier, 2010-11) Rassmann, S.; Reid, R.G.; Paskaramoorthy, S.
    This paper focuses on the mechanical and water absorption properties of kenaf fibre reinforced polyester laminates manufactured by resin transfer moulding. Varying processing conditions were considered as alternatives to fibre treatments, thereby potentially avoiding additional cost and complexity in the manufacturing process. Laminates were produced by altering fibre moisture content, mould temperature and mould pressure following injection. Tensile, flexural, impact and water absorption tests were conducted. Processing conditions were found to have little effect on properties except for pressurisation which increased tensile and flexural strength and decreased water absorption at low fibre volume fractions. Examinations using a scanning electron microscope showed that all the laminates failed by fibre pull-out.
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    Measurement of the Distribution of Residual Stresses in Layered Thick-Walled GFRP Pipes.
    (Springer, 2014-11) Carpenter, H.W.; Reid, R.G.; Paskaramoorthy, R.
    The objective of this study is to measure the axial, circumferential, shear and radial residual stress distributions in three thick-walled glass fibre reinforced plastic (GFRP) filament-wound pipes, two of which are layered. The measurement of residual stresses was carried out using a recently published layer removal method which overcomes the limitations of previous techniques and can be applied to layered anisotropic pipes of any wall thickness. Layers of approximately 0.3 mm thickness were incrementally ground from the outer surface of the pipes. The resulting strains were measured on the inner surfaces. A least-squares polynomial was fitted to each measured data set, and used to calculate the corresponding stress distributions. All of the resulting axial, hoop and shear stress distributions adhere to the requirement of self-equilibrium and the radial stress distributions all vanish to zero at the inner and outer surfaces. The radial stresses of the layered pipes showed a tendency to have two peaks, one for each layer, a consequence of the two-stage manufacturing process of these pipes. The measured axial and hoop stresses of all three pipes were similar at the inner surfaces despite significant differences in the stiffnesses in the principal directions arising from different wind angles.