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Showing 1 to 20 of 47 for “"Hopkinson Pressure Bar"”.
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Numerical investigation of dispersion in Hopkinson Pressure Bar
The Hopkinson Pressure Bar (HPB) is used as a load-time or displacement-time transducer in impact or blast experiments. The Split Hopkinson Pressure Bar (SHPB) is the accepted form of material testing for strain rates between 102 S-I and 104 S-I. Explicit Finite Element Analysis (FEA) codes are …
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Assessing the effect of friction on compression split Hopkinson pressure bar tests
… accurate high strain rate material data. A Split Hopkinson Pressure Bar (SHPB) facility had previously been developed at the University of Cape Town to allow high strain rate testing of materials in compression. However, uncertainties regarding aspects of the test method that can affect the …
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An Optical Method of Strain Measurement in the Split Hopkinson Pressure Bar
The split Hopkinson pressure bar (SHPB) continues to be one of the most common methods of testing materials at medium rates of strain. Elevated rates of strain, such as those found in impact and explosive applications, have been shown to induce phenomena such as strain hardening and phase …
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High strain rate mechanical characterization of trabecular bone utilizing the split-Hopkinson pressure bar technique
The split-Hopkinson pressure bar (SHPB) technique has been in use in one form or another for more than fifty years and has recently gained a great deal of attention for its ability to characterize materials such as metals, plastics, and even stiff foams at strain rates of up to 105 sec-1. …
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Development and proving of a split Hopkinson pressure bar used for high strain rate materials testing
… To overcome these limitations the split Hopkinson pressure bar (SHPB) was developed. A SHPB facility was developed at UCT to measure material properties at high strain rates. The development, discussed in this thesis, included the design and manufacturing of a SHPB, strain gauge …
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High-Strain Rate Tensile Characterization Of Graphite Platelet Reinforced Vinyl Ester Based Nanocomposites Using Split-Hopkinson Pressure Bar
… are performed applying the reverse impact Split Hopkinson Pressure Bar (SHPB) technique. The specimen geometry for tensile test is parametrically optimized by Finite Element Analysis (FEA) using ANSYS Mechanical APDL®. Uniform stress distribution within the specimen gage length has been verified …
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Investigation of blunt injuries and the force associated with a skull fracture due to impact with a Hopkinson pressure bar : an animal model
… were impacted with an aluminium striker bar that resembles the dimensions of a hammer (length: 23cm, circumference: 40cm and weight: 200g). The aim of these hammer tests were to characterise soft and hard tissue wound morphology as a result of blunt cranial impacts. Resulting data was …
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Investigation of wound characteristics and the force associated with skull fracture due to impact by a hammer
… The remaining specimens were impacted with a Hopkinson pressure bar of the same diameter as the striker in the hammer tests. The Hopkinson pressure bar apparatus allows for the determination of the force of impact. The use of the Hopkinson pressure bar to determine fracture forces in whole …
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Low to high strain rate deformation of amorphous polymers : experiments and modeling
… a servo-hydraulic testing machine and a split-Hopkinson pressure bar. Tension tests on the DMA were used to characterize the time-temperature dependence of the elastic storage moduli and the loss factors of the two polymers. The DMA data provided a quantification of the rate-dependent shift of …
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Development of a High Strain-Rate Constitutive Model for Sands and its Application in Finite Element Analysis of Tunnels Subjected to Blast
… triaxial compression test and split Hopkinson pressure bar test. The model is implemented in the finite element software Abaqus through user defined material subroutines. Finite element simulations of the split Hopkinson pressure bar experiments on Ottawa and Fontainebleau sands are …
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Characterisation of Glass Fibre Polypropylene and GFPP based Fibre Metal Laminates at high strain rates
… were conducted on GFPP using a compressive Split Hopkinson Pressure Bar (SHPB) and a Direct Impact Hopkinson Pressure Bar (DIHPB), in the through-thickness and in-plane directions. In both loading directions, the peak stress of GFPP increased linearly with the logarithm of strain rate. For …
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Failure of Microelectromechanical Systems Under Dynamic Loading: An Experimental and Numerical Investigation
… were conducted using the modified split hopkinson pressure bar to investigate the effects of loading amplitude, duration, and profile on the failure of the cantilever beams. Finite element simulations of these beams were conducted to provide more detailed information regarding the …
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Implementation of viscoelastic Hopkinson bars
… soft or low impedance materials using metallic bars in a split Hopkinson pressure bar setup, poor signal to noise ratios and impedance mismatching occur. One solution is to use polymeric Hopkinson bars. In this dissertation, Polycarbonate, Polymethyl Methacrylate and Nylon are considered for use …
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MODELLING AND SIMULATION MICROMACHINING OF THE ADDITIVELY MANUFACTURED METAL PARTS
… compressive mechanical response and split-Hopkinson pressure bar tests of SLMed 316L to identify Johnson-Cook constitutive model constants; quasi-static tensile mechanical response and split-Hopkinson tensile bar tests to identify dynamic damage model constants for SLMed 316L stainless …
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Machining of additively manufactured titanium Ti-6Al-4V; cutting forces and chip morphology
… through time-consuming and costly split-Hopkinson pressure bar tests. The proposed model uses a combination of experimentally measured cutting forces and optimization methods including genetic algorithm and particle swarm optimization to find the suitable J-C parameters. Force simulation …
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Multiscale Experimental Study on the Effect of Texture and Anisotropy on the Thermomechanical Response of Zirconium
The adiabatic compression of metals in the split-Hopkinson pressure bar is associated with a rise in temperature due to the dissipation of work energy. High strain rate compression experiments on zirconium are carried out to investigate a possible dependence of dissipation on deformation mechanism. …
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Finite strain behavior of polyurea for a wide range of strain rates
… to 10/s). Second, two distinct gas-gun split Hopkinson pressure bar [SHPB] systems are employed to cover high strain rates: a nylon bar system (700/s to 1200/s) and an aluminum bar system (2300/s to 3700/s). Lastly, the rate-sensitivity for intermediate strain rates (10/s to 1000/s) is …
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