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Showing 1 to 14 of 14 for “"Hopkinson Bar"”.
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Advancements in the Split Hopkinson Bar Test
The split Hopkinson bar test is the most commonly used method for determining material properties at high rates of strain. The theory governing the specifics of Hopkinson bar testing has been around for decades. It has only been the last decade or so, however, that significant data processing …
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High strain rate properties of materials using Hopkinson bar techniques
… of these properties in the future. The split Hopkinson pressure bar is a standard apparatus used to measure the mechanical strength of materials at strain rates between 500 and 10,000 s- 1 � Measurements are performed by dynamically loading a small cylindrical specimen between two rods that …
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Experimental determination of material properties for materials subjected to high compressive strain rates
The design, fabrication and operation of a split Hopkinson bar apparatus is described. The theoretical basis for the experimental determination of material properties for materials subjected to high compressive strain rates using the split Hopkinson bar is discussed along with the assumptions made …
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The strain rate dependent mechanical properties and modelling of bovine cortical bone in compression
Conventional Hopkinson bar experiments resulted in a specimen strain rate that decreases beyond reaching a maximum value at the rise time. The variation in dynamic strain rate was rectified by shaping the Hopkinson bar input pulse with a reusable, conical striker bar. The hypothesis investigated …
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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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A Precision Experiment for the Deformation and Fracture of Blast Loaded Plates
… a central support, in the form of a Hopkinson bar, for use with a novel peripherally clamped centrally supported (PCCS) plate specimen, which allows the reaction force history at the inner boundary to be captured. Hence, in addition to the traditional impulse vs deflection data, this …
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Extending the annular in-plane torsional shear test specimen to applications at high strain rates
… were performed on a modified torsional split Hopkinson bar (TSHB) system. The TSHB system adopted a nested configuration which allowed for a longer incident bar, and thus larger obtainable strains. Two quick-release mechanisms were used, one using a novel reusable wedge and the other using …
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Ανάπτυξη αριθμητικού προτύπου για την προσομοίωση της σφυρηλάτησης με βολή σωματιδίων
… καταπόνησης μέσω της πειραματικής διάταξης Split Hopkinson Bar που σχεδιάστηκε και κατασκευάστηκε στο Εργαστήριο Τεχνολογίας και Αντοχής Υλικών, β) η ανάπτυξη βοηθητικών επιμέρους αριθμητικών μοντέλων, γ) η ανάπτυξη κινηματικών μοντέλων προσομοίωσης της ροής των σωματιδίων, δ) η ανάπτυξη κριτηρίων …
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An experimental investigation of interspecies variation in mechanical properties of cortical bone
… rate tests were performed on a modified Split Hopkinson bar setup. A Cone-in-Tube striker was used to provide a near constant strain rate during testing. The use of a momentum trapping system was investigated, but was not practically useful for the scale of specimens and strain rates …
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Mechanical properties of energetic composites
… piece of mechanical testing apparatus, the Split Hopkinson Pressure Bar (SHPB), is critically assessed in chapters 2 and 3. The gauge calibration procedure was critically evaluated; the necessity of dispersion correction was investigated; and a method for allowing for the finite specimen transit …
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Degradation behaviour of the mechanical properties of bovine cortical bone
… rate tests using a three-point bending split Hopkinson bar yield rich datasets, indicating clear trends applicable for numerical validation. Simulations utilizing dynamic compression and cross-section data exhibit encouraging correlations with experimental observations. A comparison between …
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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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Additively Manufactured Metallic Cellular Materials for Blast and Impact Mitigation
Selective laser melting (SLM) is an additive manufacturing process which enables the creation of intricate components from high performance alloys. This facilitates the design and fabrication of new cellular materials for blast and impact mitigation, where the performance is heavily influenced by …