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Showing 1 to 19 of 19 for “"Stress relaxation tests."”.
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Viscoelastic characterization of collagen-GAG scaffolds
… exhibit linear viscoelastic behavior. Tension tests were performed on dry and hydrated engineered collagen-GAG scaffolds in order to develop a stress-strain curve. Strains that fell in the linear elastic region of these curves were selected and then used in stress relaxation tests that were …
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Compression testing and measurement of material properties of a double network hydrogel
… under compressive loads in cyclic compression tests and stress relaxation tests. A viscoelastic model was applied and material properties were calculated using the experimental data. The elastic modulus of these PAAm-alginate gels was found to be 35kPa, while the viscosity, [eta], was found to …
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Determinação dos parâmetros de resistência, "Creep" e de Relaxação de Tensões de uma argila mole do Rio de Janeiro
… the preconsolidation pressure is analysed. The stress-strain curves of the triaxial tests are represented by the hyperbolic formula. The strength and stress-strain parametersare determined and compared with those of other clays. The results of triaxial tests performed on undisturbed and …
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Nonlinear Viscoelastic Behavior of Ligaments and Tendons: Models and Experiments
… ligaments and tendons was investigated. Axial stress-stretch data and stress relaxation data at different axial stretches were collected by testing rat tail tendon fascicles. The experimental results demonstrated, for the first time, that the shape of the normalized axial stress relaxation …
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The plastic behavior of predeformed ice crystals
… this difficulty, measurements were made at stress levels lower than a predeformation value in an attempt to maintain constant dislocation densities. Creep, constant strain rate, and stress relaxation tests were performed as a function of stress, strain rate, temperature, and predeformation …
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Biaxial Mechanical Behavior of Swine Pelvic Floor Ligaments: Experiments and Modeling
… the first biaxial elastic and viscoelastic tests were performed on uterosacral and cardinal ligament complexes harvested from adult female swine. Biaxial elastic testing revealed that the ligaments undergo large strains and are anisotropic. The direction normal to the upper vagina was …
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Viscoplastic Study of 3D Printed Carbon Fiber Composites
… had to be gathered from a series of tensile and stress relaxation tests. A third type of test, creep, was also performed in order to validate the model predication of creep at different temperatures and loads.</p> <p>The viscoplasticity model presented in this paper was able to get rough …
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Process-induced viscoelastic residual stress analysis of graphite/epoxy composite structures
… 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 relaxation tests was performed on fully …
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Large strain time-dependent behavior of elastomeric materials
… to the state that is approached in long time stress relaxation tests; and a second network capturing the non-linear rate-dependent deviation from the equilibrium state. The time-dependence of the second network is further assumed to be governed by the reputational motion of molecules having …
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An experimental study on time-dependent behaviour of reconstituted clayey soils in 1D and triaxial compression
… is to experimentally investigate the role of stress history, soil properties and loading system in the time-dependent strength-deformation behaviour of reconstituted clayey soils. The experimental program consists of oedometer and triaxial compression tests on compacted lightly …
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The Thermal Stabilisation of Austenite at Sub-Zero Temperatures
… between martensite transformation and stress have also been discussed in order to assess the feasibility of a stabilisation mechanism controlled by stress-relaxation.<br/>The kinetics of stabilisation have been studied using an electrical resistance technique in two 0.5% carbon steels …
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Modification of Polymer Membranes: A Study of Crosslinking and In-Situ Growth of Palladium-Containing Nanoparticles in Polymer Matrices.
… ˜24 h, whereas tensile, nanoindentation and stress-relaxation tests reveal that the material stiffens, and possesses a long relaxation time that increases, with increasing tx. Although differential scanning calorimetry shows that the glass transition temperature decreases systematically with …
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Cheddar cheese : Its texture, chemical composition and rheological properties.
… rheological properties were measured using three tests performed on an Instron Universal Testing Machine - a compression test, a cutting test and a stress relaxation test - and, where appropriate, were reported in terms of true stress and true (Hencky) strain curves. The viscoelastic properties of …
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Viscoelastic behavior of water-blown flexible polyurethane foams
… made from these foams. Three viscoelastic tests; tensile stress relaxation, compression load relaxation, and compression creep, were utilized to evaluate the behavior of these materials at constant temperature and/or relative humidity, RH. The tensile stress relaxation tests were performed …
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Linear and Nonlinear Viscoelastic Characterization of Proton Exchange Membranes and Stress Modeling for Fuel Cell Applications
… of a PEM are important for making hygrothermal stress predictions in the cyclic temperature and humidity environment of operating fuel cells. In this study, Nafion® NRE 211, Gore-Select® 57, and Ion Power® N111-IP were characterized under various humidity and temperature conditions. These …
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PSYCHOMETRIC PROPERTIES OF INSTRUMENTS MEASURING STRESS IN THE AGED.
… current standardized checklists used to measure stressful life events in a noninstitutionalized population aged 65-74 years of age. Previous studies, sampling from a younger aged population, have demonstrated a temporal association between an increase in stressful life events and …
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Durability and Damage Analysis of Hybrid Multiscale Composites
… viscoplastic behavior of these composites using stress relaxation and creep tests was also performed for these different composites’ configurations. A phenomenological viscoplastic model was utilized for creep prediction over long periods of time utilizing shorter stress relaxation tests. The …
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Viscoelastic Models for Ligaments and Tendons
… time, or creep, when subjected to a constant stress and a slow continuous decrease in stress over time, or stress relaxation, when subjected to a constant strain. Moreover, the loading and unloading stress-strain curves are different when the tissues are subjected to cyclic loading, showing …
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Elevated temperature mechanical properties of line pipe steels
… of the line pipe steels. Strain rate jump tests (cycling of strain rates during deformation) were performed to measure the temperature dependence on the instantaneous strain rate sensitivities. Stress relaxation tests were used to measure the internal/effective stress components of the flow …