Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 9 of 9 for “"stress rupture"”.
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Stress rupture of unidirectional polymer matrix composites in bending at elevated temperatures
A new method for stress-rupture experiments in bending has been developed and used to characterize unidirectional polymer matrix composites. The method. which makes use of very simple fixtures, led to coherent results. These results have been modeled using the large deflection of buckled bars …
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Scaling Effects on Damage Development, Strength, and Stress-Rupture Life on Laminated Composites in Tension
… monitor damage developments. First-ply failure stress, and tensile strength were recorded. First-ply failure of the midplane 90 deg. plies depended on the stiffness of constraint plies, and size. All 24 cases were predicted using Zhang's shear-lag model and data generated from cross-ply tests. …
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Blending of polyethylene materials for pipe applications
… In this thesis studies are reported on the stress rupture performance of pipes produced from selected polyethylene materials blended to a chosen MDPE pipe grade. The pipes were tested, notched or unnotched, at a single temperature of 80oC and at internal pressures designed to induce …
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The mechanical behaviour of polyethylene pipe systems
… has been based on data mainly obtained from stress rupture testing pipes only. In practice, installations are composed of both extruded pipe and injection moulded fittings which are joined by a fusion welding technique and are very often subjected to internal pressures of a fluctuating …
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Micromechanics-Based Strength and Lifetime Prediction of Polymer Composites
… is an effort to predict the strength and rupture lifetime of a unidirectional carbon fiber/polymer matrix composite using micromechanical techniques. Sources of material variability are incorporated into these models to predict probabilistic distributions for strength and lifetime. This …
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The long-term behaviour of butt fusion welds in polyethylene pipeline systems
… on the basic material's properties. Fatigue and stress-rupture lifetimes were found to decrease significantly with increasing axial misalignment at the butt fusion weld in 63,90 and 125mm MDPE pipe systems at 79°C in a water environment. In the butt fusion weld having axial misalignment of 20 per …
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A study of the recrystallization and the mechanical properties of indium
… Metallographic techniques were developed and stress rupture data were obtained.</p> <p>Single crystals of indium were grown in a horizontal furnace with a traveling temperature zone, and sectioned in a strain-free manner, with an etch-cutter. Because of the low recrystallization temperature of …
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Durability of Ceramic Matrix Composites at Elevated Temperatures: Experimental Studies and Predictive Modeling
… ceramic matrix composite system under stress-rupture conditions were studied both experimentally and analytically. A rupture model for unidirectional composites which incorporates fiber strength statistics, fiber degradation, and matrix damage was derived. The model is based on a …
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A structural health monitoring system for composite pressure vessels
… cuts and gouges, impact and delaminations, stress rupture, heat damage, and combinations of these damage mechanisms. The damage detection system was capable of detecting damage long before a critical condition arose for all cases. However, further development and testing into larger cylinder …