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Showing 1 to 15 of 15 for “"unidirectional composite"”.
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Failure processes in unidirectional composite materials
Failure processes in unidirectional composite materials subjected to quasi-static tensile load along the fiber direction are investigated. The emphasis in this investigation is to identify the physical processes taking place during the evolution of failure in these materials. An extensive …
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Autohesion model for thermoplastic composites
… specimen, a 64-ply graphic (Thomel T300)/P1700 unidirectional composite, and a 192-ply graphite (Hercules AS4)/P1700 unidirectional composite. A 64-ply T300/P1700 unidirectional composite was processed in a matched metal mold. Temperature data were taken and compared with the calculated values. …
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Measurement of ultrasonic wave mode transition in unidirectional graphite/epoxy composites
… mechanism of mode transitions was studied in unidirectional composite materials. Theoretical calculations were compared with experimental measurements. Mode transitions occur when the wave vector orientation is varied in unidirectional samples of T300/5208 graphite/epoxy composite with a 0.6 …
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Interaction of acoustic waves and anisotropic multilayered composite plates immersed in water.
… wave propagation in multilayered anisotropic composite plates is presented. Reflection and transmission coefficients as a function of the plane wave incident angle and ultrasonic wave frequency are computed for single layered and multilayered plates. From the minima of the reflection spectra …
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Micromechanics-Based Strength and Lifetime Prediction of Polymer Composites
With the increasing use of composite materials for diverse applications ranging from civil infrastructure to offshore oil exploration, the durability of these materials is an important issue. Practical and accurate models for lifetime will enable engineers to push the boundaries of design and make …
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Mechanical response of unidirectional Boron/Aluminum under combined loading
… were employed to characterize the response of unidirectional Boron/Aluminum metal matrix composite material under monotonic and cyclic loading conditions, namely: Iosipescu Shear, Off-Axis Tension and Compression. The characterization of the elastic and plastic response includes the elastic …
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Tensile and uniaxial/multiaxial fatigue behavior of ceramic matrix composites at ambient and elevated temperatures
Increasing use of fiber reinforced ceramic matrix composites (CMC's) materials is needed, especially for hostile environments such as elevated temperatures. However, some fundamental issues regarding how these materials should be made for optimized performance are far from being settled. This study …
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The compressive behaviour of unidirectional carbon fibre reinforced plastic
… investigation into the compressive strength of unidirectionally reinforced carbon fibre composites when loaded parallel to the fibres. A comprehensive review of previous research is presented and from this it is clear that no overall theory e,d.sts for predicting the unidirectional compressive …
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Investigation of Design, Manufacture, Analysis, and Test of a Composite Connecting Rod Under Compression
<p>Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements …
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Exploring the link between microstructure statistics and transverse ply fracture in carbon/epoxy composites
Damage evolution within polymer matrix composites (PMCs) is difficult to characterize, as variability arises in the material microstructure from manufacturing and in the local strength of the constituents, which is inherently statistical. Transverse failure of unidirectional plies is particularly …
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Analysis of matrix damage in single fiber composites
<p>"A unidirectional fiber-reinforced composite under a tensile load in the direction of the fibers develops equal axial strains in the fiber and the matrix, if there are no initial cracks and the fiber/matrix interface is perfectly bonded. With further increase in the load, the fiber or the matrix …
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An analytical and experimental study of crack extension in center- notched composites
… center notch of arbitrary orientation in a unidirectional composite material. The bulk of the analytical work of this study applies an elasticity solution for an infinite plate with a center line crack to obtain critical stress and crack growth direction predictions. An elasticity solution …
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Fiber fracture in continuous-fiber reinforced composite materials during cyclic loading
The final tensile fracture of any composite structure is primarily due to the failure of its constituents, namely fibers and matrix in the present case. To date, no experimental data exists, to the author’s knowledge, to define the behavior of constitutive fibers of a composite structure throughout …
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A micromechanical model for predicting tensile strength
A novel micromechanical model for predicting the failure of polymeric and ceramic matrices under an applied global tensile loading is presented. The model is based on a Weibull statistical type of approach and incorporates eleven different variables to simulate different micromechanical failure …
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Fundamental Studies In the Lamb-Wave Interaction Between Piezoelectric Wafer Active Sensor and Host Structure During Structural Health Monitoring
… in this dissertation is that of guided waves in composite materials. The increasing use of composites in aeronautical and space applications makes it important to extend SHM theory to such materials. For this reason, the NME theory is extended to the case of composites. We developed a generic …