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Showing 1 to 20 of 27 for “"Time Temperature Superposition Principle"”.
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Long-term creep modeling of wood using time temperature superposition principle
… were developed from short-term data using the time temperature superposition principle (TTSP) for kiln-dried southern pine loaded in compression parallel-to-grain and exposed to constant environmental conditions (~70°F, ~9%EMC). Short-term accelerated creep (17 hour) and recovery (35 hour) data …
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Development of tension and compression creep models for wood using the time-temperature superposition principle
… for wood in tension and compression using the Time-Temperature Superposition Principle (TTSP). The principle states that the long-term response of a polymer at lower temperature is equivalent to the short-term response at a higher temperature. Accelerated creep tests were conducted in tension …
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The nonlinear viscoelastic behavior of adhesives and chopped fiber composites
… procedures of Schapery in conjunction with the time-temperature superposition principle to obtain a time-stress-temperature surface to define failure.
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Understanding the effect of nanofillers on the properties of polypropylene and glass fiber/polypropylene multiscale composites
… between the tensile modulus, glass transition temperature and the amount of constrained phase, as assessed through tensile and DMA analyses, revealed the presence of a secondary reinforcing mechanisms, which, concurrently to the primary stiffening effect of the high modulus filler, contributes …
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Viscoelastic characterization of angle ply advanced composites
Time dependent properties of angle ply laminated Boron/Epoxy and Graphite/Epoxy fiber controlled composites were investigated. The main objective of this study was to develop a technique to establish interconversion of different test results using appropriate viscoelastic theory to formulate an …
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Analysis and Modeling of the Mechanical Durability of Proton Exchange Membranes Using Pressure-Loaded Blister Tests
… of Gore-Select® series 57 over a range of times, temperatures, and loading histories. Ramped pressure tests are used with a linear viscoelastic analog to Hencky's classical solution for a pressurized circular membrane to estimate biaxial burst strength values. Biaxial strength master curves …
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Design of Cold-In-Place Recycling using Superpave gyratory compactor
… master curves were developed for by using time-temperature superposition principle. Furthermore, the rutting resistance of all the CIR mixtures were also evaluated in term of the flow number.
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The time-temperature behavior of graphite epoxy laminates
An in-depth study on the time-temperature behavior of epoxy based continuous and elastic fiber reinforced composite materials and the feasibility of using the time-temperature analogy as an accelerated characterization method to predict the long-term behavior are presented. This is a two-pronged …
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Modeling the High Strain Rate Tensile Response and Shear Failure of Thermoplastic Composites
… from 10^-4/s to 10^-1/s and shifted using the time-Temperature Superposition Principle (tTSP) to strain rates of 10^-4/s to 10^6/s. Other fiber properties are obtained from the same tests, but are assumed to be deterministic. Matrix properties are also assumed to be deterministic and are …
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Thermoviscoelastic characterization and predictions of Kevlar/epoxy composite laminates
… ([0]₈, [10]₈, and [90]₁₆) lamina specimens. The Time-Temperature-Superposition-Principle (TTSP) was used successfully to accelerate the characterization process. A nonlinear constitutive model was developed to describe the stress dependent viscoelastic response for each of the material …
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Characterization and Lifetime Performance Modeling of Acrylic Foam Tape for Structural Glazing Applications
… rupture testing results provided the failure time at a given static load and temperature, and ramp-to-fail testing results provided the ultimate load resistance at a given rate of strain and temperature. Parallel testing was conducted on three structural silicone sealants to compare …
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Rate and time dependent behavior of structural adhesives
… stress. A region of elastic behavior, a rate and time dependent region, and a region of perfectly plastic flow are identified in the stress-strain behavior. Information regarding variations of Poisson's ratio with rate and time is also presented. The elastic limit stress and strain, and maximum …
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Characterization of the Interfacial Fracture of Solvated Semi-Interpenetrating Polymer Network (S-IPN) Silicone Hydrogels with a Cyclo-Olefin Polymer (COP)
… for the measurement of fracture properties over time in environments of interest. In this case, the test was performed at discrete temperatures within range of 4Ë C to 80Ë C. Two COP adherends were bonded together by a layer of one of the S-IPN silicone hydrogels. Upon the insertion of a wedge …
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Wetlaid Cellulose Fiber-Thermoplastic Hybrid Composites - Effects of Lyocell and Steam Exploded Wood Fiber Blends
… modulus-building efficiency (by as much as 2.6 times) in the hybrid composites. This observation indicated possible synergism between lyocell and SEW. Analyses of composite property gains as a function of fiber cost also showed greater cost benefits (highest for tensile modulus) in favor of …
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Performance Evaluation and Durability Studies of Adhesive Bonds
… those required during a conventional "one at a time" characterization approach, potentially offering a significant reduction in characterization times. The second chapter investigates the adhesive fracture resistance and crack path selection in adhesive joints containing patterns of discreet …
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Determination of the complex modulus of a solid propellant and random vibration analysis of the layered viscoelastic cylinders with finite element method
… analyzer system was used together with time-temperature superposition principle to obtain the frequency-dependent dynamic viscoelastic properties of the solid propellant. The strain energy approach has been used to calculate the frequency-dependent equivalent viscoelastic damping which …
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Wood/Polymeric Isocyanate Resin Interactions: Species dependence
… was quantitatively analyzed by both the time-temperature superposition principle and the Kohlrausch-Williams-Watts equation. The presence of a small but statistically significant species effect was observed on both the cure chemistry and bond morphology of wood-PMDI system at low cure …
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A methodology for developing high damping materials with application to noise reduction of railway track
… but this is inevitably linked to a strong temperature-dependence<br/>of the dynamic properties. A methodology is developed that allows a material to be formulated<br/>for a particular damping application where temperature-dependence has to be<br/>taken into account. The methodology is …
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The effect of physical aging on the creep response of a thermoplastic composite
… with a service life in excess of 60,000 hours at temperature. Accurate predictions of the viscoelastic properties of the material are essential to insure that design strength and stiffness requirements are met for the entire service life. The effect of physical aging on the creep response was …
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Viscoelastic Modeling of Straight and Modified Binders at Intermediate and High Temperatures
… were tested at intermediate and high service temperatures. Short-term and long-term aging were simulated by the rolling thin film oven test and the pressure aging vessel test, respectively. A dynamic shear rheometer with parallel plate configuration was used to conduct the dynamic mechanical …
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