Shock waves in polycrystalline iron by Kadau, K, Germann, T, Lomdahl, P, Albers, R, Wark, J, Higginbotham, A, Holian, B

Shock waves in polycrystalline iron. by Kadau, K, Germann, T, Lomdahl, P, Albers, R, Wark, J, Higginbotham, A, Holian, B

“…The propagation of shock waves through polycrystalline iron is explored by large-scale atomistic simulations. …”

Shock waves in polycrystalline iron: Plasticity and phase transitions by Gunkelmann, N, Bringa, E, Tramontina, DR, Ruestes, C, Suggit, M, Higginbotham, A, Wark, J, Urbassek, H

“…However, while experiments in polycrystals show clear evidence that the α-ε transition is preceded by plasticity, simulations up to now could not detect any plastic activity occurring before the phase change. Here we study shock waves in polycrystalline Fe using an interatomic potential which incorporates the α-ε transition faithfully. …”

Femtosecond measurement of shock wave driven twinning and lattice dynamics by Wehrenberg, C, McGonegle, D, Bolme, C, Higginbotham, A, Lazicki, A, Lee, H, Nagler, B, Park, H, Remington, B, Rudd, R, Sliwa, M, Suggit, M, Swift, D, Tavella, F, Zepeda-Ruiz, L, Wark, J

“…<p>Pressure-driven shock waves in solid materials can cause extreme damage and deformation. …”

In situ X-ray diffraction measurement of shock-wave-driven twinning and lattice dynamics by Wehrenberg, C, McGonegle, D, Bolme, C, Higginbotham, A, Lazicki, A, Lee, H, Nagler, B, Park, H, Remington, B, Rudd, R, Sliwa, M, Suggit, M, Swift, D, Tavella, F, Zepeda-Ruiz, L, Wark, J

“…<p>Pressure-driven shock waves in solid materials can cause extreme damage and deformation. …”

In-situ probing of lattice response in shock compressed materials using x-ray diffraction by Hawreliak, J, Butterfield, M, Davies, H, El-Dasher, B, Higginbotham, A, Kalantar, D, Kimminau, G, McNaney, J, Milathianaki, D, Murphy, W, Nagler, B, Park, N, Remington, B, Thorton, L, Whitcher, T, Wark, J, Lorenzana, H

“…We have successfully used laser produced plasma x-ray sources coincident with laser driven shock waves to make in-situ measurements of the lattice response during shock compression for both single crystal and polycrystalline materials. …”

Picosecond X-ray diffraction studies of shocked single crystals - art. no. 62610T by Wark, J, Belak, J, Collins, G, Colvin, J, Davies, H, Duchaineau, M, Eggert, J, Germann, T, Hawreliak, J, Higginbotham, A, Holian, B, Kadau, K, Kalantar, D, Lomdahl, P, Lorenzana, H, Meyers, M, Murphy, W, Park, N, Remington, B, Rosolankova, K, Rudd, R, Schneider, MS, Sheppard, J, Stolken, J

“…One area of physics which has benefited particularly from these advances is the the field of shock-waves. Whilst it has been known for many years that crystalline matter, subjected to uniaxial shock compression, can undergo plastic deformation and, for certain materials, polymorphic phase transformations, it has hitherto not been possible to observe the rearrangement of the atoms on the pertinent timescales. …”

Molecular dynamics simulations of shock-induced deformation twinning of a body-centered-cubic metal by Higginbotham, A, Suggit, M, Bringa, E, Erhart, P, Hawreliak, J, Mogni, G, Park, N, Remington, B, Wark, J

“…We present here large scale MD simulations of shock compressed bcc metal, using an extended Finnis-Sinclair potential for tantalum, and demonstrate the presence of significant deformation twinning for pressures above the Hugoniot elastic limit for shock waves propagating along the [001] direction. The twinned variants are separately identified by a per atom order parameter, allowing the strain and stress states of the rotated material to be studied. …”

Picosecond X-ray diffraction studies of shocked single crystals by Wark, J, Belak, J, Collins, G, Colvin, J, Davies, H, Duchaineau, M, Eggert, J, Germann, T, Hawreliak, J, Higginbotham, A, Holian, B, Kadau, K, Kalantar, D, Lomdahl, P, Lorenzana, H, Meyers, M, Murphy, W, Park, N, Remington, B, Rosolankova, K, Rudd, R, Schneider, MS, Sheppard, J, Stolken, J

“…One area of physics which has benefited particularly from these advances is the the field of shock-waves. Whilst it has been known for many years that crystalline matter, subjected to uniaxial shock compression, can undergo plastic deformation and, for certain materials, polymorphic phase transformations, it has hitherto not been possible to observe the rearrangement of the atoms on the pertinent timescales. …”

Simulations of shock-induced phase transitions in silicon by Mogni, G

“…<p>An understanding of the fundamental mechanism behind the relief of shear stress in single-crystal silicon subject to loading by shock-waves has to this day remained elusive. What is known is that this material undergoes a first-order pressure-induced polymorphic phase transition from its ambient pressure cubic-diamond (<em>cd</em>) crystal structure to its first stable high-pressure phase, known as <em>β</em>-Sn, at a pressure of about 120 kbar under hydrostatic compression. …”

Picosecond X-ray diffraction from laser-shocked copper and iron by Wark, J, Belak, J, Collins, G, Colvin, J, Davies, H, Duchaineau, M, Eggert, J, Germann, T, Hawreliak, J, Higginbotham, A, Holian, B, Kadau, K, Kalantar, D, Lomdahl, P, Lorenzana, H, Meyer, M, Remington, B, Rosolankova, K, Rudd, R, Schneider, MS, Sheppard, J, Stolken, J

“…Detailed molecular dynamics calculations provide novel information about the process, and point towards methods whereby the dislocation density might be measured during the passage of the shock wave itself. We also report on recent experiments where we have obtained diffraction images from shock-compressed single-crystal iron. …”

Direct observation of the alpha-epsilon transition in shock-compressed iron via nanosecond x-ray diffraction. by Kalantar, D, Belak, J, Collins, G, Colvin, J, Davies, H, Eggert, J, Germann, T, Hawreliak, J, Holian, B, Kadau, K, Lomdahl, P, Lorenzana, H, Meyers, M, Rosolankova, K, Schneider, MS, Sheppard, J, Stölken, J, Wark, J

“…Previous identification of this transition in shock-loaded iron has been inferred from the correlation between shock-wave-profile analyses and static high-pressure x-ray measurements. …”

Measuring stacking fault densities in shock-compressed FCC crystals using in situ x-ray diffraction by Rosolankova, K, Wark, J, Bringa, E, Hawreliak, J

“…The x-ray diffraction method thus presents a real possibility for experimental determination in real time of dislocation densities in crystals during shock wave passage. © 2006 IOP Publishing Ltd.…”

Molecular dynamics simulations of shock-induced plasticity in tantalum by Tramontina, D, Erhart, P, Germann, T, Hawreliak, J, Higginbotham, A, Park, N, Ravelo, R, Stukowski, A, Suggit, M, Tang, Y, Wark, J, Bringa, E

“…We present Non-Equilibrium Molecular Dynamics (NEMD) simulations of shock wave compression along the [001] direction in monocrystalline Tantalum, including pre-existing defects which act as dislocation sources. …”

Comparison between x-ray scattering and velocity-interferometry measurements from shocked liquid deuterium by Falk, K, Regan, S, Vorberger, J, Crowley, B, Glenzer, S, Hu, S, Murphy, C, Radha, P, Jephcoat, A, Wark, J, Gericke, DO, Gregori, G

“…The Omega laser was used to drive a planar shock wave in the cryogenically cooled deuterium, creating warm dense matter conditions. …”

Comparison between x-ray scattering and velocity-interferometry measurements from shocked liquid deuterium. by Falk, K, Regan, S, Vorberger, J, Crowley, B, Glenzer, S, Hu, S, Murphy, C, Radha, P, Jephcoat, A, Wark, J, Gericke, DO, Gregori, G

“…The Omega laser was used to drive a planar shock wave in the cryogenically cooled deuterium, creating warm dense matter conditions. …”

Simultaneous 8.2 keV phase-contrast imaging and 24.6 keV X-ray diffraction from shock-compressed matter at the LCLS by Seiboth, F, Fletcher, L, McGonegle, D, Anzellini, S, Dresselhaus-Cooper, L, Frost, M, Galtier, E, Goede, S, Harmand, M, Lee, H, Levitan, A, Miyanishi, K, Nagler, B, Nam, I, Ozaki, N, Rodel, M, Schropp, A, Spindloe, C, Sun, P, Wark, J, Hastings, J, Glenzer, S, McBride, E

“…Simultaneous PCI from the 8.2 keV fundamental X-ray beam is used to visualize and measure the transient properties of the shock wave over a 500 μm field of view. Furthermore, we demonstrate the ability to extend the reciprocal space by 5˚A−1, relative to the fundamental X-ray energy, by utilizing X-ray diffraction from the 3rd harmonic of the LCLS.…”

SUBNANOSECOND X-RAY-DIFFRACTION FROM LASER-SHOCKED CRYSTALS by Wark, J, Whitlock, R, Hauer, A, Swain, J, Solone, P

“…The relevance of the technique to some of the fundamental problems of shock-wave physics and phase transitions is discussed. © 1989 The American Physical Society.…”

Picosecond X-ray diffraction from shock-compressed metals by Rosolanková, K, Rosolankova, Katarina K.

“…In particular, the need for a measurement of dislocation densities during the shock wave passage through a crystal is highlighted, and a method enabling such a measurement is proposed.…”