Showing papers in "Composites Science and Technology in 1999"

TL;DR: In this paper, the stiffness of aligned short-fiber composites is evaluated by comparison with finite-element calculations which use periodic arrays of fibers, and to Ingber and Papathanasiou's boundary element results for random arrays of aligned fibers.

TL;DR: In this article, the effect of the shrinkage state of jute fibres on the Young's modulus of composite impact damping and yarn toughness has been investigated for both untreated and treated jute/epoxy composites.

TL;DR: In this paper, the effect of chemical treatment on the tensile properties of sisal/PP composites was investigated, and it was observed that all the treatments enhanced the composites considerably, but to varying degrees.

TL;DR: In this paper, the possibility of in situ detection of damage in unidirectional CFRP by means of electric resistance measurements was investigated by changing the electrode location and conduction occurred both along the fibre and in the transverse direction by virtue of fibre-to-fibre contacts.

TL;DR: In this article, the effect of test specimen size on the unnotched strength of continuous fiber reinforced composites is considered, and different fundamental failure mechanisms of fibre direction tension, fibre direction compression, and matrix dominated transverse tension and shear are discussed in turn.

TL;DR: In this paper, the authors examined the damage in off-axis plies of composite laminates by examining the configuration [0/±θ4/01/2]s with θ=25, 40, 55, 70 and 90.

TL;DR: In this paper, a Si-B-C ceramic matrix has been developed to improve the oxidation resistance and the lifetime in an oxygen environment of carbon-fiber-reinforced ceramic-matrix composites.

TL;DR: For both monotonic and fatigue loading conditions, debonding is the subcritical micromechanism which leads to transverse cracking and ultimately influences final failure of the composite structure.

TL;DR: In this paper, a study of the microstructure of 3D braided preforms produced by the four-step 1 x 1 method is described, where an analytical approach is employed in conjunction with experimental investigation to establish the relationship between the braid structure and braiding parameters.

TL;DR: In this article, the monotonic tension, fatigue and creep properties of SiC-fiber-reinforced SiCmatrix composites (SiC/SiC) have been reviewed.

TL;DR: In this paper, an approach to analyze the tensile behavior and damage accumulation of ceramic composites is described and applied to a SiC-fiber-reinforced SiCmatrix composite.

TL;DR: In this article, the residual properties of composite laminates reinforced with two-, four-and six-layer carbon-fibre-reinforced polyimide eight-harness satin-weave fabric have been observed as a function of applied strain.

TL;DR: In this article, the authors derived closed-form expressions relating stiffness changes to the transverse crack density and derived a stress-perturbation function that is proportional to the normalized average crack-opening displacement.

TL;DR: In this paper, two types of glass-fibre-reinforced polyester composites have been immersed in water at different temperatures (from 30 to 100°C) and subjected to gravimetric analysis, mechanical tests, and microscopic observations.

TL;DR: In this paper, the authors investigated existing criteria for fiber microbuckling failure in a 0° unidirectional carbon-fibre-reinforced plastic (CFRP) laminate loaded in compression.

TL;DR: In this paper, low velocity impact tests were carried out on carbon-fabric/epoxy laminates of different thicknesses, by means of a hemispherical impactor.

TL;DR: In this article, the formation of damage doublets in adjacent carbon nanotubes embedded in a polymer matrix was observed, which may help shed light on fracture nucleation and growth in nanotube-based composites.

TL;DR: In this article, a finite multiphase element method (FMEM) was proposed to predict the effective elastic properties of 3-D braided composites, which is based on the variational principle and previous geometric model that assumes the existence of different types of unit cells in the three regions in a 3-dimensional braided composite, i.e. the interior, surface and corner.

TL;DR: In this article, an analytical model called mesotex (MEchanical Simulation Of TEXtile) is proposed to predict 3D elastic and failure properties of several woven fiber composite materials.

TL;DR: In this article, a theoretical study of elastic deformation during the compaction of woven-fabric preforms in liquid composite molding processes is presented, where the analysis focuses on the unit cell of an orthogonal plain-weave fibrous preform.

TL;DR: In this paper, an experimental study was conducted on glass/polyester quasi-unidirectional and angle-ply laminate DCB specimens with mid-plane delaminations.

TL;DR: In this article, the influence of the degree of interweaving on the mechanical performance of cylindrical structures under various loadings was investigated. But the results were limited to the case of glass/epoxy tubes with a [±55°]6 lay-up and the results showed that the undulation regions and voids found near these regions possibly represent an initiation site for cracking.

TL;DR: In this article, the friction and wear behavior of four Al/SiC p composites was investigated over a wide range of sliding conditions by the use of a specially adapted high-speed tester of the pin-on-disk configuration.

TL;DR: In this paper, a split Hopkinson pressure bar (SHPB) setup was used to test brittle, polymeric-matrix composite materials and a scheme including dispersion correction, selection of starting points, stress homogeneity and limiting strain rate has been developed.

TL;DR: In this article, the authors used the double cantilever beam (DCB) specimen for mode I, end-notched flexure (ENF) for mode II and mixed-mode bending (MMB) for I/II mixedmode loading.

TL;DR: In this article, a review of the size and scale effects involved in the prediction of strength of fiber-reinforced-plastic (FRP) composite materials and structures is presented.

TL;DR: A Japanese 100 kW automotive ceramic gas turbine (CGT) project was started in 1990 and was concluded successfully in 1997 as mentioned in this paper, which achieved higher thermal efficiency over 40% at a turbine inlet temperature of 1350°C, lower exhaust emissions to meet Japanese regulations, and multi-fuel capabilities.

TL;DR: In this article, a planar rectangular mold cavity is studied, having a single air cavity of known dimensions running along one side of the mold, all Darcy velocity components being in-plane.

TL;DR: In this paper, composites reinforced with 5, 10, 15, 20 and 20 vol% TiB2 particles were prepared by hot isostatic pressing and the properties of these specimens were evaluated.

TL;DR: In this article, the authors focused on the compression of fiber reinforcements during the processing of polymer composites, covering a range of fabrics, namely a plain weave, a twill, a satin and a non-crimped, stitch-bonded fabric.