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Showing 1 to 20 of 245 for “"High strain"”.
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High strain rate properties of structural aluminium.
… been used in the past to determine the stress-strain relationship of metals and alloys at high strain rates of up to 2.2 x 10 per second; some of these were approximate whilst others required expensive equipment. In the present study three aluminium alloys, HE15, HE30TF and DTD5044 have been …
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High Strain Rate Properties of Geological Materials
The dynamic response of various geological materials has been investigated through a series of plate impact experiments. The materials involved were supplied from various mines by De Beers and Rio Tinto and were generically termed: sandstone, scilified siltstone, kimberlite, quartz/feldspathic …
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High Strain-Rate Responses of Mechanical Metamaterials
… regime are not fully understood, especially at strain rates above 10^3 s^−1. Using microscale uniaxial compression and custom microscale Kolsky bar capabilities, we uncover the strain rate dependence of mechanical metamaterials over eight orders of magnitude, ranging from strain rates of 10^−3 …
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Dynamic Shear Bands in Metals under High Strain Rates
… applications. Analysis of these localizations highly depends on the selection of the constitutive model. Hence, two constitutive models that take temperature and strain rate effect into account are proposed. The first model is a physically based model that depends on basic physical quantities, …
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A system for high strain rate interruptible tensile tests
… used for measuring a material's response to high strain rates. High strain rate data is critical for exhaustive characterisation, due to the sensitivity of materials to the rate at which they are strained. The principle limitation of conventional SHPB is that there is limited control of the …
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Characterization of UHMWPE Laminates for High Strain Rate Applications
… effort to characterize the properties of ultra-high molecular weight polyethylene (UHMWPE). As a composite of polymers, the properties of UHMWPE are time-dependent. It is desired by research sponsors to know the properties of the material at high strain rates, in order to simulate the use of …
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Fault formation in porous sedimentary rocks at high strain rates
… faults in porous sedimentary rocks subjected to high strain rates do not form from deformation band damage zones (DBDZs) as typically observed in porous rocks. This hypothesis is evaluated by an investigation of faults mapped within the porous Navajo Sandstone at the Upheaval Dome impact …
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On the Characterization of Engineered Elastomers At High Strain Rates
… and modelling of elastomers that were subject to high-strain rate. Four aspects of the problem were accordingly examined. The first aspect of the study was dedicated to the comparison of constitutive equations to numerically model elastomers. The second aspect revolved around the testing of …
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Microstructure and texture development during high-strain torsion of NiAl
… of its characteristics. By this deformation mode high shear strains (gamma = 18 in this study) can be imposed on the sample. The deformation conditions are well-defined because of the local deformation mode, which is simple shear. Due to the monoclinic sample symmetry one half of the pole figure …
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High strain rate properties of materials using Hopkinson bar techniques
This dissertation examines the high strain rate mechanical properties of polymers, polymer bonded explosives and solders. In addition, it examines experimental developments that will allow more detailed investigation of these properties in the future. The split Hopkinson pressure bar is a standard …
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Microstructural development during high strain-rate forging of Ti-6Al-4V
Includes bibliographical references.
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Shock-wave and high strain-rate phenomena in matter: modeling and applications
… of the material response in case of high strain-rate, impact or shock loading is fundamental in several applications, such as e.g. ballistic, nuclear and military fields. The objective of the investigation of wave propagation in solids is the development of reliable methods for the …
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High-strain actuation of lead-free perovskites : compositional effects, phenomenology and mechanism
An experimental study was carried out to map the compositional dependence of electromechanical behavior and ferroelectric phase stability in the barium, zirconium-codoped sodium bismuth titanate (BNBZT) system for barium concentrations up to 18 mol.% and zirconium concentrations up to 4 mol.%. A …
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Low to high strain rate deformation of amorphous polymers : experiments and modeling
… and poly(methvl methacrylate)--at strain rates ranging from 10⁻⁴ to 10⁴ s⁻¹. This spectrum of strain rates was achieved in tension/compression tests using a dynamic mechanical analyzer (DMA), a servo-hydraulic testing machine and a split-Hopkinson pressure bar. Tension tests on the …
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Monte Carlo simulation of ion transport of high strain ionomeric polymer transducers
Ionomeric polymer transducers exhibit electromechanical coupling capabilities. The transport of charge due to electric stimulus is the primary mechanism of actuation for a class of polymeric active materials known as ionomeric polymer transducers (IPTs). The research presented in this dissertation …
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ULTRA-HIGH STRAIN RATE CONSTITUTIVE MODELING OF PURE TITANIUM USING PARTICLE IMPACT TEST
… to study materials mechanics under extremely high deformation rates, i.e., above 10^6 s^-1, a relatively less explored regime of strain rates. In this study, we accelerate microparticles of commercially pure titanium to ~100 m/s towards a rigid substrate and record their deformation upon …
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Dynamic mechanical behavior of frozen Ottawa sand subjected to high strain rate loading
Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2027-08-01
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Modeling the High Strain Rate Tensile Response and Shear Failure of Thermoplastic Composites
The high strain rate fiber direction tensile response of Ultra High Molecular Weight Polyethylene (UHMWPE) composites is of interest in applications where impact damage may occur. This response varies substantially with strain rate. However, physical testing of these composites is difficult at …
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