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Showing 1 to 18 of 18 for “"interlaminar fracture toughness"”.
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Out of autoclave manufacturing of cfrps having multiscale reinforcement for improved interlaminar fracture toughness and multifunctional characteristics
… Additionally, their low polymer matrix toughness leads to interlaminar failures such as delamination. Delaminations as a primary failure mode are resulted either from fatigue loadings or low-velocity impact which are caused by the extension of multiple matrix cracks. Therefore, …
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The Comparison of Composite Aircraft Field Repair Method (CAFRM) with Traditional Aircraft Repair Technologies
… acid digestion, short beam shear, and mode I fracture tests. The researcher was able to determine the specimen's void content, fiber volume fraction, shear strength, and opening mode interlaminar fracture toughness for the specimens fabricated using the different repair methods. The specimens …
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Effects of Voids on Delamination Behavior Under Static and Fatigue Mode I and Mode II
… over a 20 to 30 year lifetime. Delamination or interlaminar failure is a serious failure mode observed in composite structures. Even partial delamination will lead to a loss of local stiffness, which can preclude buckling failure. Manufacturing process defects such as voids and fiber waviness …
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Modeling and testing of stitched composite laminates for enhanced interlaminar strength
… percent, while it enhances the opening Mode I interlaminar fracture toughness. This degradation in the effective in-plane stiffness is attributed to the localized damage inflicted on the fiber plies by the needle penetration of the sewing machine used to insert the transversely reinforcing …
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An Investigation Into the Properties and Fabrication Methods of Thermoplastic Composites
… Tensile, compressive, and Mode I interlaminar fracture toughness tests were conducted to analyze mechanical properties of these advanced thermoplastics. Several fabrication processes were also tested to determine optimal consolidation and aesthetic appearance of structural members. …
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Interfacial strength development in thermoplastic resins and fiber-reinforced thermoplastic composites
… the ASTM tensile adhesion test (ASTM D897) and a fracture toughness test using a compact tension (CT) specimen (based on the ASTM toughness test for metals ASTM E399-83). The interfacial tensile test proved to be very difficult to perform and with an unacceptable amount of data scatter. The data …
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Mechanical Characterization Of Composite Repairs For Fiber-Glass Wind Turbine Blades
… fall off the blade. Thus the strength and toughness of the repair are of critical importance.</p> <p>Initial part of this work consists of an effort to increase repair strength by identifying an optimum hand layup repair resin for fiberglass wind turbine blades currently being manufactured …
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Systematic assessment of the influence of voids on the material performance and failure in additively manufactured polymers.
… of FFF components, with particular focus on fracture toughness and fatigue crack propagation. Various experimental techniques including fracture initiation, fatigue propagation, X-ray computed tomography (CT), fractography, thermography and digital image correlation (DIC) were adopted to …
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Fatigue Damage Prognosis of Internal Delamination in Composite Plates Under Cyclic Compression Loadings Using Affine Arithmetic as Uncertainty Propagation Tool
… using Affine Arithmetic. The Mode I and Mode II interlaminar fracture toughness and fatigue characterization of the composite plates are first experimentally studied to obtain the material coefficients and fracture toughness, respectively. Next, these obtained coefficients are used in the …
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Understanding the correlation between wrinkle morphology, fracture and fatigue of plain woven CFRP laminates through mechanical and ultrasonic characterization.
… (CFRP) laminates, can significantly alter the fracture and fatigue behavior of composite structures. This dissertation presents a comprehensive experimental investigation into the influence of out-of-plane wrinkles on interlaminar fracture toughness under both Mode I and Mode II loading …
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Toughened bismaleimides, their carbon fiber composites and interphase evaluation studies
… of employing engineering thermoplastics as toughness modifiers for Bismaleimide resins was utilized to improve the fracture toughness properties of these important materials, which have applications as matrix resins for high performance composites. Modifier molecular weight, end group …
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Multifunctionality in epoxy/glass fibers composites with graphene interphase
… flexural tests, short-beam shear tests, mode I interlaminar fracture toughness and creep tests which also confirmed that GO and rGO based interphase in epoxy/glass composites increase the performances of the composite with respect to that of the uncoated GF based composites. GO proved to be the …
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Fatigue, Fracture and Impact of Hybrid Carbon Fiber Reinforced Polymer Composites
… the effects of dispersed nanofillers on the fracture toughness of FRPs, currently, there are no literature detailing the effect of surface GSD grown CNTs and ZnO nanowire -on carbon fiber- on the fracture toughness of these hybrid composites. This dissertation probes the effects of surface …
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Next Generation Multifunctional Composites for Impact, Vibration and Electromagnetic Radiation Hazard Mitigation
… A major drawback to FRPs is their weak interlaminar properties (e.g., interlaminar fracture toughness). The need for lightweight multifunctional structures has become vital for many applications and hence alleviating the out-of-plane mechanical (i.e., quasi-static, vibration, and impact) …
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The effect of cooling rate on toughness and crystallinity in poly(ether ketone ketone) (PEKK)/G30-500 composites
… sixth panel was used to investigate changes in toughness due to manufacturing towpreg with polymer that had been reclaimed from the towpreg fabrication system’s air cleaner. Cooling rates of 2°C/min, 4°C/min, 6°C/min, and 8°C/min resulted in composites with crystallinities of 33%, 27%, 24%, and …
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Phase morphology and fracture toughness of CNT/polytherimide modified epoxy polymer nanocomposites as matrices for advanced CFPR composites
… also the primary reason for the relatively low fracture toughness of these materials. This could negatively affect the interlaminar properties of the resulting FRP composites, as the toughness of the matrix is closely related to the delamination fracture toughness of the FRP composites, making …
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Development of multifunctional polymer composites with self-healing capability
… mechanical properties. Nevertheless, acceptable fracture toughness values in quasi-static mode were obtained. Samples were thermally mended at 80 and 100 °C, and the healing efficiency (HE) was assessed by comparing the fracture toughness of virgin and repaired samples both in quasi-static and in …
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Development of self-healing techniques for fiber reinforced composites
… limitation of these composites is the poor interlaminar toughness and strength. The mismatch of anisotropic mechanical and thermal properties in between plies of deferent principal directions promotes out of plane stresses at the edges of the structures as well as in the case of stringer run …