The Experts below are selected from a list of 84 Experts worldwide ranked by ideXlab platform
J W Coenen - One of the best experts on this subject based on the ideXlab platform.
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plastic deformation of recrystallized tungsten potassium wires constitutive deformation law in the temperature range 22 600 c
International Journal of Refractory Metals & Hard Materials, 2018Co-Authors: Dmitry Terentyev, J Riesch, S Lebediev, T Khvan, A Zinovev, M Rasinski, A Dubinko, J W CoenenAbstract:Abstract Recent efforts dedicated to the mitigation of tungsten (W) brittleness have demonstrated that tungsten fiber-reinforced composites acquire extrinsic toughening even at room temperature, which is due to the outstanding strength of W wires. However, high temperature operation/fabrication of the fiber-reinforced composite might result in the degradation of the mechanical properties of W wires. To address this, we investigate mechanical and microstructural properties of potassium-doped tungsten wires, being heat treated at 2300 °C and tested in temperature range 22–600 °C. Based on the microscopic analysis, the engineering deformation curves are converted into actual stress - strain dataset, accounting for the local Necking. The analysis demonstrates that local strain in the Necking Region can reach up to 50% and the total elongation monotonically increases with temperature, while the ultimate tensile strength goes down. Preliminary transmission electron microscopy analysis using FIB-cut lamella from the Necking Region revealed the presence of curved dislocation lines in the sample tested at 300 °C, proving that plastic deformation occurred by dislocation glide.
Dimitri Debruyne - One of the best experts on this subject based on the ideXlab platform.
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identification of the post Necking hardening behaviour of sheet metal by comparison of the internal and external work in the Necking zone
Journal of Materials Processing Technology, 2011Co-Authors: Sam Coppieters, Steven Cooreman, Hugo Sol, P Van Houtte, Dimitri DebruyneAbstract:Abstract The most common way to evaluate the stress–strain relation of sheet metal is by performing standard tensile tests. However, those tests only allow the identification of the hardening behaviour up to the point of maximum uniform elongation, at least when using standard measuring equipment and simple analytical formulas to derive the relation between force and stress, and, elongation and strain. Usually the hardening behaviour beyond this point is estimated by extrapolation of the hardening behaviour before the point of maximum uniform elongation. Such procedure may yield very different results, depending on the hardening law which is fitted to the available experimental data. Other methods which deal with the problem of extended yield curve identification have been proposed and the most applied among them are finite-element based inverse approaches. This paper presents an alternative method to identify the post-Necking hardening behaviour of sheet metal without using a finite element model. The key point in the presented method is the minimization of the discrepancy between the internal and external work in the Necking zone during a tensile test. The main focus of this paper is on the presentation of the method, the underlying assumptions and the experimental validation. In addition, the method was applied to identify two common hardening laws for DC05, which is a mild deep drawing steel, using experimental data from the pre- and post-Necking Region.
Dmitry Terentyev - One of the best experts on this subject based on the ideXlab platform.
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plastic deformation of recrystallized tungsten potassium wires constitutive deformation law in the temperature range 22 600 c
International Journal of Refractory Metals & Hard Materials, 2018Co-Authors: Dmitry Terentyev, J Riesch, S Lebediev, T Khvan, A Zinovev, M Rasinski, A Dubinko, J W CoenenAbstract:Abstract Recent efforts dedicated to the mitigation of tungsten (W) brittleness have demonstrated that tungsten fiber-reinforced composites acquire extrinsic toughening even at room temperature, which is due to the outstanding strength of W wires. However, high temperature operation/fabrication of the fiber-reinforced composite might result in the degradation of the mechanical properties of W wires. To address this, we investigate mechanical and microstructural properties of potassium-doped tungsten wires, being heat treated at 2300 °C and tested in temperature range 22–600 °C. Based on the microscopic analysis, the engineering deformation curves are converted into actual stress - strain dataset, accounting for the local Necking. The analysis demonstrates that local strain in the Necking Region can reach up to 50% and the total elongation monotonically increases with temperature, while the ultimate tensile strength goes down. Preliminary transmission electron microscopy analysis using FIB-cut lamella from the Necking Region revealed the presence of curved dislocation lines in the sample tested at 300 °C, proving that plastic deformation occurred by dislocation glide.
T Khvan - One of the best experts on this subject based on the ideXlab platform.
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plastic deformation of recrystallized tungsten potassium wires constitutive deformation law in the temperature range 22 600 c
International Journal of Refractory Metals & Hard Materials, 2018Co-Authors: Dmitry Terentyev, J Riesch, S Lebediev, T Khvan, A Zinovev, M Rasinski, A Dubinko, J W CoenenAbstract:Abstract Recent efforts dedicated to the mitigation of tungsten (W) brittleness have demonstrated that tungsten fiber-reinforced composites acquire extrinsic toughening even at room temperature, which is due to the outstanding strength of W wires. However, high temperature operation/fabrication of the fiber-reinforced composite might result in the degradation of the mechanical properties of W wires. To address this, we investigate mechanical and microstructural properties of potassium-doped tungsten wires, being heat treated at 2300 °C and tested in temperature range 22–600 °C. Based on the microscopic analysis, the engineering deformation curves are converted into actual stress - strain dataset, accounting for the local Necking. The analysis demonstrates that local strain in the Necking Region can reach up to 50% and the total elongation monotonically increases with temperature, while the ultimate tensile strength goes down. Preliminary transmission electron microscopy analysis using FIB-cut lamella from the Necking Region revealed the presence of curved dislocation lines in the sample tested at 300 °C, proving that plastic deformation occurred by dislocation glide.
A Dubinko - One of the best experts on this subject based on the ideXlab platform.
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plastic deformation of recrystallized tungsten potassium wires constitutive deformation law in the temperature range 22 600 c
International Journal of Refractory Metals & Hard Materials, 2018Co-Authors: Dmitry Terentyev, J Riesch, S Lebediev, T Khvan, A Zinovev, M Rasinski, A Dubinko, J W CoenenAbstract:Abstract Recent efforts dedicated to the mitigation of tungsten (W) brittleness have demonstrated that tungsten fiber-reinforced composites acquire extrinsic toughening even at room temperature, which is due to the outstanding strength of W wires. However, high temperature operation/fabrication of the fiber-reinforced composite might result in the degradation of the mechanical properties of W wires. To address this, we investigate mechanical and microstructural properties of potassium-doped tungsten wires, being heat treated at 2300 °C and tested in temperature range 22–600 °C. Based on the microscopic analysis, the engineering deformation curves are converted into actual stress - strain dataset, accounting for the local Necking. The analysis demonstrates that local strain in the Necking Region can reach up to 50% and the total elongation monotonically increases with temperature, while the ultimate tensile strength goes down. Preliminary transmission electron microscopy analysis using FIB-cut lamella from the Necking Region revealed the presence of curved dislocation lines in the sample tested at 300 °C, proving that plastic deformation occurred by dislocation glide.
