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Showing 1 to 20 of 46 for “"Strain rate sensitivity"”.
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Investigation of strain rate sensitivity of polymer matrix composites
An investigation into high strain rate behaviour of polymer composites was performed by developing a finite element model for a fibre reinforced polymer (FRP) plates impacted at varying strain rates. The work was divided into three facets, firstly to characterize the FRP material at varying strain …
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Multi-Component Characterization of Strain Rate Sensitivity in Pharmaceutical Materials
… plastically deforming materials tend to be more strain rate sensitive than brittle materials, but this sensitivity depends on how fast the material can respond to applied stresses. In addition, since many pharmaceutical materials also demonstrate relatively large amounts of elastic deformation, …
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Role of Mechanical Stress, Excipients and Coprocessing On Tablet Mechanical Properties
… speed during tableting scale-up was evaluated. Strain rate sensitivity (SRS) of compactibility profile was examined by evaluating the effect of speed on material deformation behavior. Mechanical parameters, namely Workc/d and tablet recovery (%), were used as measures of irreversible and …
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The strain rate dependent mechanical properties and modelling of bovine cortical bone in compression
… 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 was that a …
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Elevated temperature mechanical properties of line pipe steels
… Deformation behavior, ductility, strength, strain hardening rate, strain rate sensitivity, and fracture behavior were characterized at room temperature and in the temperature range of 200-350 °C, the potential operating range for steels used in oil production by the steam assisted gravity …
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The permanent deformation of steel portal frames subjected to impulsive loading
… mode approximation technique extended to include strain-rate sensitivity, finite deflections and pulse duration. Experimental results are presented which show good agreement with theoretical predictions. The use of the extended Hamilton's principle for mode form solutions is discussed.
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Towards mechanism-based constitutive modelling of L1₂ crystal plasticity
… stress, tensioncompression asymmetry, and small strain rate sensitivity. Some ideas on revising the plasticity model have been presented. Though not completed, the new approach points to promising future directions in simulating both the yield behavior and the strain hardening properties of L12 …
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Impact resistance of high strength fiber reinforced concrete
… concrete was investigated over the full strain rate regime, from static loading to high strain rate loading, and finally to impact loading. The compressive toughness of FRC under static loading was studied using an existing Japanese standard (JSCE SF-5). Then, a test method for FRC under …
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Experimental and numerical study of primary consolidation of soft clay
… the same soil specimen is subjected to different strain rates, 2) the effects of hydraulic gradient on consolidation behavior, and 3) the scaling effects based on ... from oedometer tests with varying drainage heights. This research is separated into two main parts including the experimental …
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Experimental and theoretical investigation of constant rate of strain consolidation
The Constant Rate of Strain (CRS) test provides an efficient and a relatively rapid method to determine properties (stress history, compressibility, hydraulic conductivity, and rate of consolidation) of a cohesive soil and possess many advantages over the incremental oedometer test. Ease of …
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Effect of ion irradiation on the rate dependence of plastic deformation of extruded Zr-2.5%Nb
… temperature, material properties such as the strain hardening, strain rate sensitivity and apparent activation volume were investigated. The effects of Zr+ ion-implantation occurring at 300°C, simulating irradiation-induced damage, and the strain rate of loading on these properties were also …
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A Numerical Investigation of Loading Rate Effects on Pre-Cracked Charpy V-Notch Specimens
To quantify the effects of loading rate on ductile crack growth in CVN specimens, plane strain, finite element analyses are used to model ductile crack extension in specimens subjected to quasi-static and impact loading. The Gurson-Tvergaard dilatant plasticity model for voided materials describes …
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Extraction of mechanical properties over a range of strain rates from indentation data
… procedure has been applied for the study of rate-dependent plasticity in bulk metallic materials. Ballistic impact (indentation) of hard spherical projectiles was used to study a rigidly held target, with operative strain rates of the order 105 s-1. Input for the FEM model includes data …
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Kinetics of Plastic Flow in Polycrystal Plasticity
… that considers the kinetics of plastic flow. Strain rate and temperature dependencies, included in the single crystal constitutive response, are based on the isotropic mechanical threshold stress continuum model. A modified power law is used to determine slip system activity without …
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A numerical study of the response of blast loaded thin circular plates, with both clamped and integral boundary conditions
… of plate response have assumed a fully constrained boundary condition, while experiments have involved the use of both clamped and integral (fully built-in) boundary conditions. The current analysis employs 4-noded continuum elements in the finite element model, that allow the experimental …
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Finite strain behavior of polyurea for a wide range of strain rates
… as its high toughness-to-density ratio and high strain rate-sensitivity, so its application is recently extended to structural purpose to form sandwich-type or multi-layered plates. Those structures can be used for retrofitting of military vehicles and historic buildings, absorbing energy during …
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An elastic-plastic interface constitutive model for combined normal and shear loading : application to adhesively bonded joints
… a variety of separation and slide loading modes, strain rates, and thermal conditions are of interest in many technical areas. An elastic-plastic constitutive model for adhesive interfaces subjected to combined normal and shear loading has been developed and numerically implemented in a finite …
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Response of thin circular plates to central blast loading
… element code. The finite element code incorporates non-linear geometry and material effects as well as strain rate sensitivity. A material failure model is also incorporated. The SA.XI axisymmetric sheet elements are used to model the plate. The shell element uses a theory that includes shear …
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Cryomilling and Spark Plasma Sintering of 2024 Aluminium Alloy
… sintering due to the localized overheating generated by the sparks and low thermal stability of the material. It is well known that a bimodal microstructure reveals an improvement of ductility which is the most critical characteristics of nanostructured metals. In a simplistic view, …
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Freeze casting of bioactive glass and ceramic scaffolds for bone tissue engineering
… along the orientation direction, with large strain for failure (greater than 20%) and strain rate sensitivity. For a similar porosity, the bioactive glass scaffolds had a higher strength than the HA scaffolds, presumably because of better sintering characteristics. Columnar bioactive glass …
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