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Y M Gupta - One of the best experts on this subject based on the ideXlab platform.
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sound velocities in shock compressed soda lime glass melting and liquid state response
Physical Review B, 2021Co-Authors: P. Renganathan, Thomas S Duffy, Y M GuptaAbstract:Longitudinal sound velocities (and elastic moduli) were determined in soda lime glass (SLG) at peak shock stresses ranging between 40 and 90 GPa. Laser interferometry was used to obtain particle velocity histories and sound velocities by impacting SLG samples on lithium fluoride (LiF) optical windows. In all experiments, the SLG response consists of a sharp jump to a constant state followed by a Release Wave. The measured longitudinal sound velocities and moduli showed a marked decrease between 52 and 58 GPa, providing experimental evidence for the transformation from an amorphous solid to a liquid in shock-compressed SLG. The stress threshold (\ensuremath{\sim}55 GPa) for melting in SLG is considerably lower than the threshold reported in shock-compressed fused silica (\ensuremath{\sim}72 GPa), showing the effect of network-modifying cations on the onset of melting. The relative values of sound velocities, shock velocities, and the Hugoniot slopes---between 58 and 90 GPa---are fully consistent with the thermodynamic response of a shock-compressed liquid. Using the experimental results, the Gr\"uneisen parameter (\ensuremath{\Gamma}) values were determined for liquid SLG to 90 GPa and then used to provide the Mie-Gr\"uneisen equation of state for liquid SLG.
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shock compression and Release of a axis magnesium single crystals anisotropy and time dependent inelastic response
Journal of Applied Physics, 2017Co-Authors: P. Renganathan, J M Winey, Y M GuptaAbstract:To gain insight into inelastic deformation mechanisms for shocked hexagonal close-packed (hcp) metals, particularly the role of crystal anisotropy, magnesium (Mg) single crystals were subjected to shock compression and Release along the a-axis to 3.0 and 4.8 GPa elastic impact stresses. Wave profiles measured at several thicknesses, using laser interferometry, show a sharply peaked elastic Wave followed by the plastic Wave. Additionally, a smooth and featureless Release Wave is observed following peak compression. When compared with Wave profiles measured previously for c-axis Mg [Winey et al., J. Appl. Phys. 117, 105903 (2015)], the elastic Wave amplitudes for a-axis Mg are lower for the same propagation distance, and less attenuation of elastic Wave amplitude is observed for a given peak stress. The featureless Release Wave for a-axis Mg is in marked contrast to the structured features observed for c-axis unloading. Numerical simulations, using a time-dependent anisotropic modeling framework, showed tha...
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shock Wave compression and Release of hexagonal close packed metal single crystals inelastic deformation of c axis magnesium
Journal of Applied Physics, 2015Co-Authors: J M Winey, P. Renganathan, Y M GuptaAbstract:To understand inelastic deformation mechanisms for shocked hexagonal-close-packed (hcp) metals, shock compression and Release Wave profiles, previously unavailable for hcp single crystals, were measured for c-axis magnesium crystals. The results show that the elastic-inelastic loading response is strongly time-dependent. Measured Release Wave profiles showed distinct peaked features, which are unusual for inelastic deformation during unloading of shocked metals. Numerical simulations show that pyramidal slip provides a reasonably good description of the inelastic loading response. However, {101¯2} twinning is needed to explain the unloading response. The results and analysis presented here provide insight into the relative roles of dislocation slip and deformation twinning in the response of shocked hcp metals.
P. Renganathan - One of the best experts on this subject based on the ideXlab platform.
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sound velocities in shock compressed soda lime glass melting and liquid state response
Physical Review B, 2021Co-Authors: P. Renganathan, Thomas S Duffy, Y M GuptaAbstract:Longitudinal sound velocities (and elastic moduli) were determined in soda lime glass (SLG) at peak shock stresses ranging between 40 and 90 GPa. Laser interferometry was used to obtain particle velocity histories and sound velocities by impacting SLG samples on lithium fluoride (LiF) optical windows. In all experiments, the SLG response consists of a sharp jump to a constant state followed by a Release Wave. The measured longitudinal sound velocities and moduli showed a marked decrease between 52 and 58 GPa, providing experimental evidence for the transformation from an amorphous solid to a liquid in shock-compressed SLG. The stress threshold (\ensuremath{\sim}55 GPa) for melting in SLG is considerably lower than the threshold reported in shock-compressed fused silica (\ensuremath{\sim}72 GPa), showing the effect of network-modifying cations on the onset of melting. The relative values of sound velocities, shock velocities, and the Hugoniot slopes---between 58 and 90 GPa---are fully consistent with the thermodynamic response of a shock-compressed liquid. Using the experimental results, the Gr\"uneisen parameter (\ensuremath{\Gamma}) values were determined for liquid SLG to 90 GPa and then used to provide the Mie-Gr\"uneisen equation of state for liquid SLG.
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shock compression Release of magnesium single crystals along a low symmetry orientation role of basal slip
Journal of Applied Physics, 2019Co-Authors: P. Renganathan, Yogendra M. GuptaAbstract:To gain insights into the relative contributions of different plastic deformation mechanisms, particularly basal slip, for shocked hexagonal close-packed (hcp) metals, magnesium (Mg) single crystals were subjected to shock compression and Release along a low-symmetry (LS) orientation to 1.9 and 4.8 GPa elastic impact stresses. LS-axis is a “nonspecific” direction resulting in propagation of quasilongitudinal and quasishear Waves. Wave profiles, measured using laser interferometry, show a small elastic Wave followed by two plastic Waves in compression; Release Wave profiles exhibited a structured response for the higher stress and a smooth response for the lower stress. The LS-axis Wave profiles are significantly different than profiles published previously for c- and a-axes, demonstrating that Mg single crystals exhibit strong anisotropy under shock compression/Release. Numerical simulations, using a time-dependent anisotropic modeling framework, show that shock Wave loading along the LS-axis involves the simultaneous operation of multiple deformation mechanisms. Shock compression along LS-axis is dominated by basal slip while prismatic slip and pyramidal I { 10 1 ¯ 1 } ⟨ 11 2 ¯ 3 ⟩ slip play a smaller role; coupling between longitudinal and shear deformations was observed. The unloading response is dominated by basal slip with some contribution from prismatic slip; pyramidal I slip is not activated. The present results, unlike results obtained for c- and a-axes, show that the deformation mechanism observed under quasistatic loading conditions along LS-axis is not sufficient to determine the shock response along this orientation. Although requiring numerical simulations for Wave analysis, shock propagation along a LS-orientation provides new insights into the plastic deformation response of hcp metal single crystals.To gain insights into the relative contributions of different plastic deformation mechanisms, particularly basal slip, for shocked hexagonal close-packed (hcp) metals, magnesium (Mg) single crystals were subjected to shock compression and Release along a low-symmetry (LS) orientation to 1.9 and 4.8 GPa elastic impact stresses. LS-axis is a “nonspecific” direction resulting in propagation of quasilongitudinal and quasishear Waves. Wave profiles, measured using laser interferometry, show a small elastic Wave followed by two plastic Waves in compression; Release Wave profiles exhibited a structured response for the higher stress and a smooth response for the lower stress. The LS-axis Wave profiles are significantly different than profiles published previously for c- and a-axes, demonstrating that Mg single crystals exhibit strong anisotropy under shock compression/Release. Numerical simulations, using a time-dependent anisotropic modeling framework, show that shock Wave loading along the LS-axis involves the...
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shock compression and Release of a axis magnesium single crystals anisotropy and time dependent inelastic response
Journal of Applied Physics, 2017Co-Authors: P. Renganathan, J M Winey, Y M GuptaAbstract:To gain insight into inelastic deformation mechanisms for shocked hexagonal close-packed (hcp) metals, particularly the role of crystal anisotropy, magnesium (Mg) single crystals were subjected to shock compression and Release along the a-axis to 3.0 and 4.8 GPa elastic impact stresses. Wave profiles measured at several thicknesses, using laser interferometry, show a sharply peaked elastic Wave followed by the plastic Wave. Additionally, a smooth and featureless Release Wave is observed following peak compression. When compared with Wave profiles measured previously for c-axis Mg [Winey et al., J. Appl. Phys. 117, 105903 (2015)], the elastic Wave amplitudes for a-axis Mg are lower for the same propagation distance, and less attenuation of elastic Wave amplitude is observed for a given peak stress. The featureless Release Wave for a-axis Mg is in marked contrast to the structured features observed for c-axis unloading. Numerical simulations, using a time-dependent anisotropic modeling framework, showed tha...
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shock Wave compression and Release of hexagonal close packed metal single crystals inelastic deformation of c axis magnesium
Journal of Applied Physics, 2015Co-Authors: J M Winey, P. Renganathan, Y M GuptaAbstract:To understand inelastic deformation mechanisms for shocked hexagonal-close-packed (hcp) metals, shock compression and Release Wave profiles, previously unavailable for hcp single crystals, were measured for c-axis magnesium crystals. The results show that the elastic-inelastic loading response is strongly time-dependent. Measured Release Wave profiles showed distinct peaked features, which are unusual for inelastic deformation during unloading of shocked metals. Numerical simulations show that pyramidal slip provides a reasonably good description of the inelastic loading response. However, {101¯2} twinning is needed to explain the unloading response. The results and analysis presented here provide insight into the relative roles of dislocation slip and deformation twinning in the response of shocked hcp metals.
J M Winey - One of the best experts on this subject based on the ideXlab platform.
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shock compression and Release of a axis magnesium single crystals anisotropy and time dependent inelastic response
Journal of Applied Physics, 2017Co-Authors: P. Renganathan, J M Winey, Y M GuptaAbstract:To gain insight into inelastic deformation mechanisms for shocked hexagonal close-packed (hcp) metals, particularly the role of crystal anisotropy, magnesium (Mg) single crystals were subjected to shock compression and Release along the a-axis to 3.0 and 4.8 GPa elastic impact stresses. Wave profiles measured at several thicknesses, using laser interferometry, show a sharply peaked elastic Wave followed by the plastic Wave. Additionally, a smooth and featureless Release Wave is observed following peak compression. When compared with Wave profiles measured previously for c-axis Mg [Winey et al., J. Appl. Phys. 117, 105903 (2015)], the elastic Wave amplitudes for a-axis Mg are lower for the same propagation distance, and less attenuation of elastic Wave amplitude is observed for a given peak stress. The featureless Release Wave for a-axis Mg is in marked contrast to the structured features observed for c-axis unloading. Numerical simulations, using a time-dependent anisotropic modeling framework, showed tha...
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shock Wave compression and Release of hexagonal close packed metal single crystals inelastic deformation of c axis magnesium
Journal of Applied Physics, 2015Co-Authors: J M Winey, P. Renganathan, Y M GuptaAbstract:To understand inelastic deformation mechanisms for shocked hexagonal-close-packed (hcp) metals, shock compression and Release Wave profiles, previously unavailable for hcp single crystals, were measured for c-axis magnesium crystals. The results show that the elastic-inelastic loading response is strongly time-dependent. Measured Release Wave profiles showed distinct peaked features, which are unusual for inelastic deformation during unloading of shocked metals. Numerical simulations show that pyramidal slip provides a reasonably good description of the inelastic loading response. However, {101¯2} twinning is needed to explain the unloading response. The results and analysis presented here provide insight into the relative roles of dislocation slip and deformation twinning in the response of shocked hcp metals.
Yogendra M. Gupta - One of the best experts on this subject based on the ideXlab platform.
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shock compression Release of magnesium single crystals along a low symmetry orientation role of basal slip
Journal of Applied Physics, 2019Co-Authors: P. Renganathan, Yogendra M. GuptaAbstract:To gain insights into the relative contributions of different plastic deformation mechanisms, particularly basal slip, for shocked hexagonal close-packed (hcp) metals, magnesium (Mg) single crystals were subjected to shock compression and Release along a low-symmetry (LS) orientation to 1.9 and 4.8 GPa elastic impact stresses. LS-axis is a “nonspecific” direction resulting in propagation of quasilongitudinal and quasishear Waves. Wave profiles, measured using laser interferometry, show a small elastic Wave followed by two plastic Waves in compression; Release Wave profiles exhibited a structured response for the higher stress and a smooth response for the lower stress. The LS-axis Wave profiles are significantly different than profiles published previously for c- and a-axes, demonstrating that Mg single crystals exhibit strong anisotropy under shock compression/Release. Numerical simulations, using a time-dependent anisotropic modeling framework, show that shock Wave loading along the LS-axis involves the simultaneous operation of multiple deformation mechanisms. Shock compression along LS-axis is dominated by basal slip while prismatic slip and pyramidal I { 10 1 ¯ 1 } ⟨ 11 2 ¯ 3 ⟩ slip play a smaller role; coupling between longitudinal and shear deformations was observed. The unloading response is dominated by basal slip with some contribution from prismatic slip; pyramidal I slip is not activated. The present results, unlike results obtained for c- and a-axes, show that the deformation mechanism observed under quasistatic loading conditions along LS-axis is not sufficient to determine the shock response along this orientation. Although requiring numerical simulations for Wave analysis, shock propagation along a LS-orientation provides new insights into the plastic deformation response of hcp metal single crystals.To gain insights into the relative contributions of different plastic deformation mechanisms, particularly basal slip, for shocked hexagonal close-packed (hcp) metals, magnesium (Mg) single crystals were subjected to shock compression and Release along a low-symmetry (LS) orientation to 1.9 and 4.8 GPa elastic impact stresses. LS-axis is a “nonspecific” direction resulting in propagation of quasilongitudinal and quasishear Waves. Wave profiles, measured using laser interferometry, show a small elastic Wave followed by two plastic Waves in compression; Release Wave profiles exhibited a structured response for the higher stress and a smooth response for the lower stress. The LS-axis Wave profiles are significantly different than profiles published previously for c- and a-axes, demonstrating that Mg single crystals exhibit strong anisotropy under shock compression/Release. Numerical simulations, using a time-dependent anisotropic modeling framework, show that shock Wave loading along the LS-axis involves the...
J R Asay - One of the best experts on this subject based on the ideXlab platform.
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compressive strength measurements in aluminum for shock compression over the stress range of 4 22 gpa
Journal of Applied Physics, 2005Co-Authors: H Huang, J R AsayAbstract:Measurements of the high-pressure compressive strength are presented for several aluminum alloys shocked to 22GPa. Five well-characterized aluminum materials were studied, including 6061 alloy with three average grain sizes (50, 30, and <5μm), pure aluminum 1060 (99.5% Al) with a 180-μm grain size, and ultrapure aluminum (99.9998% Al) with a 300-μm grain size. The purpose of these experiments was to investigate deformation mechanisms responsible for the apparently anomalous quasielastic recompression previously observed and to determine how the shock-induced yield strength varies with initial properties. The yield strength was estimated using combined reshock and Release techniques previously developed. These results show that quasielastic recompression occurs for all materials investigated and is independent of grain size and impurity level. The shear stress and the shear strength at the shocked state were estimated from the reshock and Release Wave profiles. These results are consistent with previous in...