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We present and evaluate a semiempirical particle-based model of electrophoretic deposition using extensive mesoscale simulations. We analyze particle configurations in order to observe how colloids accumulate at the electrode and arrange into deposits. In agreement with existing continuum models, the thickness of the deposit increases linearly in time during deposition. Resulting colloidal deposits exhibit a transition between highly ordered and bulk disordered regions that can give rise to an appreciable density gradient under certain simulated conditions. The overall volume fraction increases and falls within a narrow range as the driving force due to the electric field increases and repulsive intercolloidal interactions decrease. We postulate ordering and stacking within the initial layer(s) dramatically impacts the microstructure of the deposits. We find a combination of parameters, i.e., electric field and suspension properties, whose interplay enhances colloidal ordering beyond the commonly known approach of only reducing the driving force. [ABSTRACT FROM AUTHOR]

Recent nanomechanical tests on submicron metal columns and wires have revealed a dramatic increase in yield strength with decreasing sample size. Here, we demonstrate that nanoporous metal foams can be envisioned as a three-dimensional network of ultrahigh-strength nanowires, thus bringing together two seemingly conflicting properties: high strength and high porosity. Specifically, we characterized the size-dependent mechanical properties of nanoporous gold using a combination of nanoindentation, column microcompression, and molecular dynamics simulations. We find that nanoporous gold can be as strong as bulk Au, despite being a highly porous material, and that the ligaments in nanoporous gold approach the theoretical yield strength of Au.