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Showing 1 to 20 of 34 for “"Damage Development"”.
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Damage development in fiber composites due to bearing
Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1983.
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Structural response and damage development of cylindrical composite panels
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1997.
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Damage development and failure of fiber-reinforced ceramic matrix composites
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1989.
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Monitoring Progressive Damage Development in Laminated Fiber Reinforced Composite Materials
… of growing importance in engineering practice. Damage development in composite materials is more complex than for metallic materials, because in composite materials (a) multiple damage modes are simultaneously in play, and (b) individual 'damage events' that occur throughout a component's …
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Damage Development in Static and Dynamic Deformations of Fiber-Reinforced Composite Plates
… delamination between adjoining layers, and damage due to fiber breakage, fiber/matrix debonding, and matrix cracking. The three damage modes are modeled using the theory of internal variables and the delamination by postulating a failure envelope in terms of the transverse stresses; the …
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Damage development under compression-compression fatigue loading in a stitched uniwoven graphite/epoxy composite material
Damage initiation and growth under compression-compression fatigue loading were investigated for a stitched uniweave material system with an underlying AS4/3501-6 quasi-isotropic layup. Performance of unnotched specimens having stitch rows at either 0° or 90° to the loading direction was compared. …
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Scaling Effects on Damage Development, Strength, and Stress-Rupture Life on Laminated Composites in Tension
The damage development and strength of ply-level scaled carbon/epoxy composite laminates having stacking sequence of [+Tn/-Tn/902n]s where constraint ply angle, T, was 0, 15, 30, 45, 60, and 75 degrees, and size was scaled as n=1,2,3, and 4, is reported in Part I. X-radiography was used to monitor …
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The development and application of the load-stroke hysteresis technique for evaluating fatigue damage development in composite materials
… loop area) is directly related to the (damage) events that alter material properties and life, and (4) a quantitative measure of damage extent and development is obtained.
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Transmitted light intensity as a nondestructive evaluation technique for glass/epoxy composite laminates
… to their multilithic nature and complex failure. Development of new techniques, which are more cost-effective and practical, are needed. Transmitted light intensity has the potential to satisfy these criteria. By measuring light intensity transmitted through a composite sample during fatigue …
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Mechanical behavior and damage mechanisms of woven graphite-polyimide composite materials
… tested. Material properties were measured and damage development documented under monotonic tension, sustained incremental tension, and tension-tension fatigue loading. Damage evaluation techniques included stiffness monitoring, penetrant-enhanced X-ray radiography, laminate deply, and residual …
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Acousto-Ultrasonic Evaluation of Cyclic Fatigue of Spot Welded Structures
… approach is used to explore the damage development in tensile shear spot welds during fatigue loading. There is reasonable data to support the hypothesis that a decrease in an AU signal is indicative of the presence of an internal crack and could be used for monitoring and …
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Ermittlung des Verformungs- und Schädigungsverhaltens von Wärmedämmschichtsystemen
… by the lack of systematic data concerning the damage development, and of the material properties that affect it. In the present work, the damage development in a TBC system has been investigated under simulated service conditions. The system consisted of an atmospheric plasma sprayed, yttrium …
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Damage analysis and mechanical response of as-received and heat-treated Nicalon/CAS-II glass-ceramic matrix composites
Experimental results of damage development in and mechanical response of heat-treated NicaloniCAS-II laminates subjected to monotonic flexure and axial loading and to cyclic tensile loading are reported. The specimens were subjected to post-processing heat treatments at 900°, 1000°, and l100°C in …
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Stiffness reduction resulting from transverse cracking in fiber- reinforced composite laminates
Several damage modes, including fiber breakage, delamination, and transverse cracking, have been observed to contribute to the mechanical degradation of fiber-reinforced composite laminates. In this investigation, the effect of transverse cracking on laminate stiffness was studied. Four. …
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Characterizing Damage Evolution and Yield in Sandstone Under Triaxial Loading as a Function of Various Effective Pressure
… Yielding and accumulation of microscopic damage at sub-critical stress levels however also are important characteristic of the failure process. Here, load-reload triaxial compression tests are used to investigate damage development at low and high effective pressures, and validate …
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Experimental and Numerical Analysis of Damage in Notched Composites
… in order to investigate the effect of fatigue damage development on the residual properties. Quasi-static tests were initially performed on notched composites using digital image correlation (DIC) to determine the strain profiles at selected transverse sections of the outer ply of the laminates …
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A method for in situ SEM fracture studies of brittle materials using the double torsion technique : application to nuclear graphite
This work concerned the design and development of a miniature double torsion (DT) testing rig, for use inside the chamber of a scanning electron microscope, to perform in situ loading studies of brittle materials using the DT fracture mechanics specimen. The in situ performance of the system inside …
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Fatigue response of notched graphite--epoxy laminates
… were recorded and related to the fatigue damage. Two different laminates [0,90,+45,-45]s (type A) and [ +45, 90, -45, 0] s (type B) were considered and the effects of stacking sequence were compared. Nondestructive testing techniques such as X-radiography, moire technique, acoustic …
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The effect of thickness on the fracture behavior of graphite/bismaleimede laminates with central circular holes
… on the stress distribution around the hole. Damage development around the holes was studied using x-ray radiography. In general, the small holes created more damage than the large holes and the thin laminates were more susceptible to damage than the thick laminates. All notched specimens …
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Fatigue behavior of notched carbon epoxy laminates during reversed cyclic loads
The relationships between fatigue damage, stress redistribution, and residual stiffness and strength were investigated for notched graphite epoxy laminates during fulIy-reversed cyclic loads. Two material systems, AS4/3501-6 and AS4/1808, two lamination arrangements, (0,45,90,-45)<sub>s</sub>₄ and …
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