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Showing 1 to 15 of 15 for “"Cross-ply laminates"”.
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SMA-induced deformations in unsymmetric cross-ply laminates
… SMA-induced deformations in an unsymmetric cross ply laminate. A previously developed theory is used to predict the room-temperature shape of the cross-ply laminate by minimizing its total potential energy. Then, using the principle of virtual work, equations relating the shape of the …
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Effect of fiber/Matrix Interphase on the Long Term Behavior of Cross-Ply Laminates
… effects n the mechanical properties of composite laminates. Three material systems having the same Apollo graphite fibers and HC 9106-3 toughened epoxy matrix, but with different fiber surface treatments and sizings were used in this study. The fibers used in the 810A and 820 A systems received …
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Elastic and time dependent matrix cracking in cross-ply composite laminates
… of time and stress level were investigated in cross-ply laminates to gain more understanding on the damage events in composites. Analytical predictions of the effect of stress level were performed for the case of linear elastic materials. The predictions were based on energy methods and linear …
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Characteristics of thermally-induced transverse cracks in graphite-epoxy composite laminates
… transverse cracks in T300/5208 graphite-epoxy cross-ply and quasi-isotropic laminates were investigated both experimentally and analytically. The formation of transverse cracks and the subsequent crack spacing present during cooldown to -250°F (116K) and thermal cycling between 250 and -250°F …
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Transverse microcracking in Celion 6000 graphite/PMR-15 polyimide composite
… (TVM) in Celion 6000/PMR-15 graphite-epoxy laminates were investigated. Microcracks were observed using a replicating technique, microscopy and x-ray. The mechanical or thermal load at which microcracking initiates and the ply residual stresses were predicted using laminate analysis with …
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Nonlinear temperature dependent failure analysis of finite width composite laminates
… stress analysis of finite width composite laminates including curing stresses is presented. Cross-ply, angle-ply, and some quasi-isotropic graphite/epoxy, laminates are studied. Curing stresses are calculated using temperature dependent elastic properties that are input as percent retention …
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Finite element analysis of damaged cross-ply composite laminates
… of transverse cracks in T300/5208 graphite-epoxy cross-ply laminates was studied using generalized plane strain finite element analysis. The degradation of elastic modulus, Poisson's ratio, shear modulus, and coefficient of thermal expansion was predicted and then compared with analytical models …
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Fatigue Microcracking of Composite Material IM7/977-2
… experiments in fatigue were run on IM7/977-2 cross-ply laminates. Using a modified Paris Law approach, microcracking fatigue data is presented over a wide range of applied cyclic stresses. This Paris Law plot shows an "A" value of 6.40x10-25 and a "B" value of 8.07 and provides a complete …
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Resistance of Carbon Fibre Reinforced Composites to Quasi-static and Ballistic Perforation
… of carbon fibre reinforced plastic (CFRP) cross-ply laminates were investigated under quasi-static and ballistic loading. In this thesis, the two most prominent failure modes were indirect tension and shear plugging. To characterise the indirect tension mechanism, CFRP cross-ply coupons …
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Deformations of In-plane Loaded Unsymmetrically Laminated Composite Plates
… focuses on the response of flat unsymmetric laminates to an inplane compressive loading that for symmetric laminates are of sufficient magnitude to cause bifurcation buckling, postbuckling, and secondary buckling behavior. In particular, the purpose of this study is to investigate whether or …
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Analysis of Composite Laminates with Matrix Cracks
… of the effects of matrix cracking on composite laminates is a well-known problem which has attracted considerable attention for the past decade. An approximate analytical solution is introduced in this thesis to study this type of problem. The subjects of primary concern are the degradation of …
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Evaluation of efficiency of partial hybrid finite element method using composite laminates with crack
… interior delamination crack tips in composite laminates subjected to out-of-plane loading. The stress field consisting of both in-plane and out-of-plane components around a through thickness edge crack in a laminated composite under uniaxial tension is also studied. The cracked composite …
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Deformations of Unsymmetric Composite Panels
… axial-stiff, and circumferentially-stiff laminates are considered. These panels are intended to be symmetric laminates, but are slightly unsymmetric due to the manufacturing anomalies. Rayleigh-Ritz and finite-element models are developed to predict the deformations. Initially, to serve as …
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Investigation of Microcracking and Damage Propagation in Cross-Ply Composite Laminates
… IM7/977-2, IM7/5555, and IM7/5276-1 [0/90/90/0] laminates. For each material system, seven to eight small coupons were axially loaded in a tensile substage. At increments of around 50 MPa the surfaces of the specimens were inspected via optical microscopy so that a history of microcracking damage …
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The effect of environmental aging/exposure on the durability of high performance polymeric composites
… It was also seen that residual stresses in cross-ply laminates were sufficient to trigger ESC after exposure to common organic solvents for an hour. The damage/failure modes were captured by SEM micrographs.