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Showing 1 to 20 of 21 for “"Johnson-Cook"”.
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Implementation of material models for high strain rate applications as user-subroutines in abaqus/explicit
… the implementation and verification of the Johnson-Cook and Zerilli-Armstrong material models as VUMATs. The same version of the Johnson-Cook material model is contained in Abaqus and was therefore used as a benchmark. These material models are suitable for high strain, high strain rate and …
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MODELLING AND SIMULATION MICROMACHINING OF THE ADDITIVELY MANUFACTURED METAL PARTS
… 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 steel; experiments of the micro machining process to study …
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ULTRA-HIGH STRAIN RATE CONSTITUTIVE MODELING OF PURE TITANIUM USING PARTICLE IMPACT TEST
… impacts using two constitutive equations: Johnson-Cook and Zerilli-Armstrong. We show that titanium microparticles experience strain rates in the range of 10^6-10^10 s^-1 upon impact. We evaluate the capability of the Johnson-Cook and Zerilli-Armstrong equations in predicting material …
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Simulace obráběcích operací pomocí explicitní MKP
… jeho popis podľa materiálového modelu plasticity Johnson-Cook. Posledná časť práce sa zaoberá analýzou matematických prístupov využívaných v MKP a simuláciou obrábacieho procesu pri zvolených rezných podmienkach.
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Large strain computational modeling of high strain rate phenomena in perforating gun devices by Lagrangian/Eulerian FEM simulations
… interest is addressed to reviewing the so-called Johnson-Cook strength model, by critically highlighting its positive and negative aspects. One of the main tackled issue consists in a reasoned assessment of the various procedures adoptable in order to calibrate the parameters of the model. This …
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Výroba kolíkové koncovky objemovým tvářením
… pričom pretvárny odpor bol určený podla modelu Johnson-Cook. Celková pretvárna sila vyšla 64,5 kN a pretvárna práca 189 J. Následne bola vypracovaná výkresová dokumentácia prietlačníku a prietlačnice pre dopredné pretlačenie drieku a zástavbový výkres pracovného priestoru stroja Šmeral TPM 5, …
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Machining of additively manufactured titanium Ti-6Al-4V; cutting forces and chip morphology
… Ti-6Al-4V and presents a model to determine Johnson Cook (J-C) constitutive parameters from complex machining processes through numerical modeling and experimental validation. The J-C parameters are important in describing the characteristics and behaviors of materials during high-strain rate …
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Finite element analysis of failure modes in dynamically loaded pre-cracked steel plates
… of the notch ligament. The computations employed Johnson - Cook model which takes into account strain hardening, strain-rate hardening and thermal softening. An approximate solution of the governing equations is sought by using an explicit finite element code DYNA2D. We analyzed the evolution of …
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Finite volume modelling of low speed structural impact problems
… materials. We demonstrate how the rate dependent Johnson-Cook plasticity model is crucial to ensure correspondence to experiment. The second investigation is concerned with the application of EFVM to simulate impact damage to thin polymeric coatings applied to the surface of metals. The aim of …
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Analytical model for force prediction when machining metal matrix composites
… orthogonal metal cutting mechanics and the Johnson-Cook Equation. The ploughing force was formulated while the fracture force was calculated from the slip line field theory and the Griffith theory of failure. The predicted results were compared with previously measured data. The results …
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Modeling and Simulation of Viscoplasticity, Recrystallization, and Softening of Alloyed Steel During Hot Rolling Process
… curves. Viscoplastic models including a Johnson-Cook (JC) model, a Zerilli-Armstrong (ZA) model, and a combined JC and ZA model were developed. Dynamic recrystallization behavior was investigated and modeled based on single hot compression test. Work hardening rate curve and dynamic …
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The Constitutive Behavior of Copper at High Strain Rate as Determined by the Free Expansion Ring Test
… rate sensitivity of the material at this stage. Johnson Cook and Zerilli Armstrong constitutive models are fitted to the experimental data and it can be concluded that one constitutive law is unable to describe the nature of the material in the conditions present in this technique.
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Taylor Impact Test and Penetration of Reinforced Concrete Targets by Cylindrical Composite Rods
… response of steel and copper is modeled by the Johnson-Cook relation and the ceramic and concrete are assumed to be elastic-plastic. Values of material parameters in the constitutive relation for the reinforced concrete (RC) are derived by the rule of mixtures. Failure of a material is simulated …
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Simulación computacional y medición experimental de dureza de un recubrimiento de aluminio producido por cold spray
… material a través del modelo de plasticidad de Johnson-Cook. Con este modelo se calcula el esfuerzo de fluencia por endurecimiento y se relaciona dicho esfuerzo con la dureza del material mediante relaciones empíricas. En las simulaciones, el tamaño de partícula utilizado es de 25 m y la …
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Effect of Material and Geometric Parameters on Deformations of a Dynamically loaded Prenotched Plate
… of the material are modeled by the Johnson-Cook relation. The effect of different material parameters, notch-tip radius, impact speed and the length of the projectile on the maximum tensile principal stress and the initiation and propagation of shear bands at the notch-tip is …
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Finite Element Analysis of Thermoviscoplastic Deformations of an Impact-Loaded Prenotched Plate
… relations, namely, the Litonski-Batra, the Johnson-Cook, the Bodner-Partom and the power law are used to model the thermoviscoplastic response of a material. Each one of these relations accounts for strain hardening, strain-rate hardening and thermal softening of the material. The material …
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Extraction of mechanical properties over a range of strain rates from indentation data
… by a single parameter value (C in the Johnson–Cook formulation), convergence on its optimum value is straightforward, although a parameter characterizing interfacial friction is also required. Using experimental data from (both work-hardened and annealed) copper samples, this procedure …
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Investigations of Hypervelocity Impact Physics
… comparison of material models indicated that the Johnson-Cook and Steinberg-Cochran-Guinan-Lund metallic formulations yielded the most consistent results with the lowest deviation from experimental measures in the strain rate regime of interest. Both meshless Lagrangian and quasi-Eulerian meshed …
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The Effects of Laser Shock Peening on the Residual Stress and Corrosion Characteristics of Magnesium Alloy AZ91D for use as Biodegradable Implants
There is a continuing interest in exploring magnesium and its alloys for biomedical applications due to its low density and high strength properties that are very similar to bone. However, the high corrosion rate of magnesium and its alloys while immersed in body fluid restrict the material from …
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