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Showing 1 to 20 of 82 for “"Epoxy Composite"”.
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Energy Absorption Capacity of Graphite-Epoxy Composite Tubes
… capacity of a series of axially crushed composite tubes fabricated from high tow count graphite fiber is compared with those of similar tubes fabricated from aerospace-grade fiber to determine the viability of considering the use of such fibers in automotive applications. To that end, …
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Enviro-Mechanical Durability of Graphite/Epoxy Composite Materials
Carbon/epoxy laminates are receiving greater attention by the infrastructure, marine, and offshore oil industries due to the need for superior performance capabilities. Such applications generally involve subjecting materials to harsh temperature and moisture conditions. The objective of this study …
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Thermoviscoelastic characterization and predictions of Kevlar/epoxy composite laminates
… characterization of Kevlar 49/Fiberite 7714A epoxy composite lamina and the development of a numerical procedure to predict the viscoelastic response of any general laminate constructed from the same material. The four orthotropic material properties, S₁₁, S₁₂, S₂₂, and S₆₆, were characterized …
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Delamination growth in graphite/epoxy composite laminates under tensile loading
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1994.
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Process-induced viscoelastic residual stress analysis of graphite/epoxy composite structures
… behavior of thermoset matrix fiber-reinforced composites on process-induced residual stresses was investigated. The material selected for study was AS4/3501-6, a commercial prepreg system manufactured by Hercules, Inc. To investigate the cure-dependent viscoelastic behavior, a series of stress …
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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 …
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Microcracking Fracture Toughness for Graphite Epoxy Composite Laminates Using Finite Fracture Mechanics
<p>Graphite/epoxy composite laminates are widely used in the aerospace industry. However the industry cannot take full advantage of the superior strength and stiffness of composite materials until their failure mechanisms can be thoroughly understood by engineers. Recognizing the importance of such …
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The effects of space radiation on a chemically modified graphite- epoxy composite material
… of a chemically modified T300/934 graphite-epoxy composite system. The material was subjected to 1.0 x 10¹⁰ rads of 1.0 MeV electron irradiation under vacuum to simulate 30 years in geosynchronous earth orbit. Monotonic tension tests were performed at room temperature (75° F /24° C) and …
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Transmitted light intensity as a nondestructive evaluation technique for glass/epoxy composite laminates
… evaluation method for inspection of composite materials is a difficult process due 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 …
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Investigation the effect of expanded graphite modification on tensile properties and adhesive of epoxy composite
… and adhesive toughness of unmodified graphite composite and to investigate the effects of its modification on the properties of epoxy composite. Two facile approaches of producing the expanded graphite were performed: thermal expansion and sonication process. Since epoxy polymer and graphite …
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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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Investigation of Microcrack Growth in [0/90]s Graphite Epoxy Composite Laminates Using X-Ray Microtomography
Graphite epoxy composites are being used in aerospace industry and spacecraft applications for their light weight and high strength. As a matter of fact these materials also have some disadvantages like damage which is hazardous when used in cryogenic application. Composite materials IM7/977-2, …
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Imbedded optical fiber sensor of differential strain and temperature in graphite/epoxy composites
… of strain and temperature in graphite-epoxy composite materials using differential interferometry is described. The sensor uses two single-mode optical fiber waveguides imbedded within the composite during prepreg ply lay-up. Strain and temperature changes arc obtained as a motion of an …
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Durability of Chopped FiberReinforced Polymeric Composites for use in Experimental Automotive Fuel Cells
… the durability of fiber reinforced polymer (FRP) composite materials. Automotive fuel cell power train systems must prove themselves as a reliable alternative to the combustion engines and automatic transmissions. The use of polymer composites in fuel cells to serve as manifolds is promising …
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Predicting failure behavior of polymeric and asphalt composites using damage models
… the failure behavior of two types of composite materials using damage models within the framework of ABAQUS finite element software. The failure behavior of an IM7/977-2 carbon epoxy composite material subjected to a Mode I delamination is predicted using traction-separation and bulk …
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Compressive strength of lamina reinforced and fiber reinforced composite materials
… of lamina reinforced and fiber reinforced composite materials when loaded parallel to the reinforcement. An analytical model which replaces the fiber reinforced composite with a laminate containing initially curved laminae has been proposed. By applying the Timoshenko beam equations to each …
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Studies of dielectric breakdown under pulsed power conditions
… particularly titanium oxide and ceramic/epoxy composite materials, are being characterized and studied. Results of research to-date show that the dense titania ceramics with nanocrystalline grain size (~200 nm) exhibit significantly higher electrical BDS as compared to ceramics made using …
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Self-sealing of thermal fatigue and mechanical damage in fiber-reinforced composite materials
Fiber reinforced composite tanks provide a promising method of storage for liquid oxygen and hydrogen for aerospace applications. The inherent thermal fatigue of these vessels leads to the formation of microcracks, which allow gas phase leakage across the tank walls. In this dissertation, …
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Stochastic J-integral and realiability of composite laminates based on a computational methodology combining experimental investigation, stochastic finite element analysis and maximum entropy method
… behavior and the reliability of laminated composites. A computational approach combining the Stochastic Finite Element Method (SFEM), the Maximum Entropy Method (MEM), and experimental investigation has been developed. Using this approach, the fracture parameters including the Stress …
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