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Showing 1 to 20 of 109 for “"Fiber orientation"”.
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Improved Fiber Orientation Predictions for Injection Molded Composites
Our new orientation model is aphenomenological theory, and the value of the scalar factor to reduce the orientation change rate is determined by matching experimental data. Since the rheology of a fiber suspension is affected by the fiber orientation, a rheological experiment measuring the shear …
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Prediction of Fiber Orientation During Processing of Short Fiber Composites
The fiber orientation pattern created by the flow of a suspension of short fibers controls the physical and mechanical properties of a short fiber composite material. The orientation of the fibers at any point in the composite plays the role of a structural state variable. Two sets of even-order …
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Numerical Predictions of Flow-Induced Fiber Orientation in Three-Dimensional Geometries
The effects of coupling the rheology and fiber orientation for a fiber suspension through a orientation-dependent viscosity were also examined. Calculations were performed for axisymmetric contraction flow, axisymmetric expansion flow, and radially diverging flow in a thin cavity. For the …
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Improved Prediction of Glass Fiber Orientation in Basic Injection Molding Geometries
… the prediction of short (SGF) and long glass fiber (LGF) orientation in a center-gated disk and end-gated plaque injection molding test geometry using a simulation method that has not been attempted previously. Previous work has used assumptions to simplify the fiber orientation geometry …
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Fiber orientation in injection-molded composites: A comparison of theory and experiment
Experimental measurements of fiber orientation are reported for two parts injection molded from nylon 6/6 reinforced with 43 weight percent of glass fibers. The parts are a center-gated disk and a film-gated strip. Orientation is measured from polished cross-sections and reported as a function of …
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Novel Apparatus to Control Electrospinning Fiber Orientation for the Production of Tissue Engineering Scaffolds
… jet axis for repeatable scaffold production. Fiber alignment and scaffold density are precisely controlled by rotating a mandrel along one axis, translation along that same axis, and rotation around the second axis perpendicular to the electrospun fiber stream. The control is accomplished with …
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Fiber Orientation Prediction and Strength Evaluation of Composite Spur Gears Reinforced by Discontinuous Fiber
… combination of the reinforcing phase (carbon fiber, alumina, etc.) and matrix phase (polymer, ceramic, metals, etc.). Carbon fiber reinforced composites are mostly used on intricate stress sensitive structures like wings of aero plane or gear. Amount of fiber, fiber type, and size of the fiber …
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Modeling and Interpretation of Fiber Orientation-Based Failure Mechanisms in Machining of Carbon Fiber-Reinforced Composites
Fiber-reinforced polymer composites have recently emerged as novel materials capable of playing a unique role in industrial applications. The advantage of these materials over traditional metals or polymers comes from the material property enhancements that can be achieved by combining appropriate …
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Experimental Evaluation and Simulations of Fiber Orientation in Injection Molding of Polymers Containing Short Glass Fibers
Injection molded short fiber reinforced composites have generated commercial interest in the manufacturing of lightweight parts used in semi-structural applications. Predicting these materials’ fiber orientation with quantitative accuracy is crucial for technological advancement, but the task is …
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Fiber Orientation Modeling: a Method to Improve Quantitation of Intramyocellular Lipids in Human Subjects at 7 Tesla
… In this work, we explore another approach, named Fiber Orientation Modeling (FOM) by using the bulk susceptibility effect theory to accurately assess the lineshape of EMCL. METHODS: The distribution of EMCL strand orientation at any angle from 0 degrees to 90 degrees relative to Bo was described …
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Effect of Stacking Sequence and Fiber Orientation on the Stress-Strain Behavior of CFRP Confined Concrete Cylinders
… to examine the effect of stacking sequence and fiber orientation on the compressive behavior of fiber reinforced polymer (FRP) confined concrete. This thesis presents the results of an experimental investigation examining the effect of parameters such as fiber orientation, amount of confinement, …
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Fiber Orientation Effects on the Fracture and Flexural Toughness of Extruded Fiber Reinforced Concrete for Additive Manufacturing
In this study, the mechanical properties of a fiber-reinforced cementitious composite (FRCC) were derived for specimens fabricated using two different methods of casting: conventional cast construction and pump-driven extrusion. Through the extrusion process, fibers are more likely to be oriented …
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Factors Affecting Fiber Orientation and Properties in Semi-Flexible Fiber Composites Including the Addition of Carbon Nanotubes
Within this research, factors affecting the orientation of injection molded long fiber composites in an end-gated plaque were investigated. Matrix viscosity was found to have a small effect on fiber orientation. The impact matrix viscosity had on orientation was dependent on fiber loading. At lower …
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Using a Sliding Plate Rheometer to Obtain Material Parameters for Simulating Long Fiber Orientation in Injection Molded Composites
… determining empirical parameters in stress and fiber orientation models required to accurately simulate the fiber orientation in injection molded composites. An independent approach aims to obtain the material parameters using a sliding plate rheometer to measure the rheology of fiber …
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Effect of interfacial thermal conductance and fiber orientation on the thermal diffusivity/conductivity of unidirectional fiber-reinforced ceramic matrix composites
The role of an interfacial barrier at the fiber-matrix interface in the heat conduction behavior of an uniaxial silicon carbide fiber-reinforced reaction-bonded silicon nitride and the effect of fiber orientation on the heat conduction characteristics of carbon fiber-reinforced borosilicate glass …
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Modeling Fiber Orientation using Empirical Parameters Obtained from Non-Lubricated Squeeze Flow for Injection Molded Long Carbon Fiber Reinforced Nylon 6,6
Long fiber reinforced thermoplastic composites are used for creating lightweight, but mechanically sound, automotive components. Injection molding is a manufacturing technique commonly used for traditional thermoplastics due to its efficiency and ability to create complex geometries. Injection …
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Heart failure and associated structural and functional remodeling: assessment employing various magnetic resonance imaging methodologies.
… been extended to study tissue microstrucure and fiber orientation in both the brain and the heart through specially designed pulse sequences which are sensitive to diffusion. In this specialized imaging method, known as diffusion tensor magnetic resonance imaging (DTMRI), myofiber orientation can …
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Interactions and orientation in concentrated suspensions of rigid rods: Theory and experiment
A theory for the processing-induced fiber orientation and stress in fiber reinforced-polymer composites is presented. Short-fiber-reinforced polymer composites are represented by concentrated suspensions of rigid rods. In concentrated suspensions, fiber-fiber contact is likely and affects the fiber …
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Modeling of Microstructures and Stiffness of Injection Molded Long Glass Fiber Reinforced Thermoplastics
… of the use of injection molded discontinuous fiber-reinforced thermoplastics. During the intensive injection molding process, severe fiber breakage arises in the plasticating stage leading to a broad fiber length distribution. Fiber orientation distribution (FOD) is another highly anisotropic …
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