A5019273741- High-Velocity Impact and Material Behavior
- Microstructure and mechanical properties
- Metal Forming Simulation Techniques
- Metallurgy and Material Forming
- High-pressure geophysics and materials
- Laser-Plasma Interactions and Diagnostics
- Energetic Materials and Combustion
- Metal and Thin Film Mechanics
- Composite Material Mechanics
- Aluminum Alloys Composites Properties
- Magnesium Alloys: Properties and Applications
- Aluminum Alloy Microstructure Properties
- Numerical methods in engineering
- Model Reduction and Neural Networks
- Laser-induced spectroscopy and plasma
- Nuclear Materials and Properties
- Ion-surface interactions and analysis
- Microstructure and Mechanical Properties of Steels
- Advanced Numerical Methods in Computational Mathematics
- Elasticity and Material Modeling
- Fluid Dynamics Simulations and Interactions
- Electromagnetic Launch and Propulsion Technology
- Nonlocal and gradient elasticity in micro/nano structures
- Rheology and Fluid Dynamics Studies
- Corrosion Behavior and Inhibition
DEVCOM Army Research Laboratory
2012-2023
United States Army Combat Capabilities Development Command
2022-2023
Studsvik (Sweden)
2013-2020
Impact Technology Development (United States)
2015
Clinical Research Institute
2012
Duke University
2012
Lawrence Livermore National Laboratory
2002-2011
University of Rostock
2010
Brown University
1986-2009
Boston University
2001
The paper presents a two-dimensional approach for simulating primary static recrystallization, which is based on coupling viscoplastic crystal plasticity finite-element model with probabilistic kinetic cellular automaton. accounts crystallographic slip and the rotation of lattice during plastic deformation. uses space time as independent variables orientation accumulated dependent variables. ambiguity in selection active systems avoided by using formulation that assumes rate system related...
We present a multiscale strength model in which depends on pressure, strain rate, temperature, and evolving dislocation density. Model construction employs an information passing paradigm to span from the atomistic level continuum level. Simulation methods overall hierarchy include density functional theory, molecular statics, dynamics, based approaches. Given nature of subcontinuum simulations upon is based, particularly appropriate rates excess 104 s−1. Strength parameters are obtained...
Experimental results showing significant reductions from classical in the Rayleigh-Taylor instability growth rate due to high pressure effective lattice viscosity are presented. Using a laser created ramped drive, vanadium samples compressed and accelerated quasi-isentropically at $\ensuremath{\sim}1\text{ }\text{ }\mathrm{Mbar}$ peak pressures, while maintaining sample solid state. Comparisons with simulations theory indicate that pressure, strain conditions trigger phonon drag mechanism,...
Nonequilibrium molecular-dynamics (MD) simulations show that shock-induced void collapse in copper occurs by emission of shear loops. These loops carry away the vacancies which comprise void. The growth continues even after they collide and form sessile junctions, creating a hardened region around collapsing scenario seen our differs from current models assume prismatic loop is responsible for collapse. We propose dislocation-based model gives excellent agreement with stress threshold found...
The effect of material path dependent hardening on neck development and the onset ductile failure is analyzed numerically. calculations are carried out using an elastic-viscoplastic constitutive relation that has isotropic kinematic behaviors as limiting cases accounts for weakening due to growth micro-voids. Final incorporated into model by dependence plastic potential void volume fraction. Results obtained both axisymmetric plane strain tension. Failure found initiate coalescence at center...
Experimental results showing significant reductions from classical in the Rayleigh–Taylor (RT) instability growth rate due to high pressure effective lattice viscosity metal foils are presented. Stabilization of RT (RTI) by ablation and density gradients has been studied for decades. The regime stabilized RTI material strength at is new. On Omega Laser Laboratory Energetics, University Rochester, target samples polycrystalline vanadium compressed accelerated quasi-isentropically ∼1 Mbar...