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Consider faceting of a crystal surface caused by strongly anisotropic surface tension, driven by surface diffusion and accompanied by deposition (etching) due to fluxes normal to the surface. Nonlinear evolution equations describing the faceting of 1+1 and 2+1 crystal surfaces are studied analytically, by means of matched asymptotic expansions for small(More)
In this paper we consider the evolution by surface diiusion of material voids in a linearly elastic solid, focusing on the evolution of voids with large surface energy anisotropy. It is well known that models for the time evolution of similar material surfaces can become mathematically ill-posed when the surface energy is highly anisotropic. In some cases,(More)
—Synchrotron X-ray computed tomography (SXCT) is increasingly being used for 3D imaging of material samples at micron and finer scales. The success of these techniques has increased interest in 4D reconstruction methods that can image a sample in both space and time. However, the temporal resolution of widely used 4D reconstruction methods is severely(More)
A method is described for quantitatively analyzing the level of interconnectivity of solid-oxide fuel cell electrode phases. The method was applied to the three-dimensional microstructure of a Ni-Y2O3-stabilized ZrO2 (Ni-YSZ) anode active layer measured by focused ion beam scanning electron microscopy. Each individual contiguous network of Ni, YSZ, and(More)
Synchrotron x-ray tomography was performed on titanium foams with aligned, elongated pores, initially created by sintering directionally freeze-cast preforms using two different powder sizes. Three-dimensional reconstructions of the pore structures were analyzed morphologically using interface shape and interface normal distributions. A smaller powder size(More)
The processes controlling the morphology of dendrites have been of great interest to a wide range of communities, since they are examples of an out-of-equilibrium pattern forming system, there is a clear connection with battery failure processes, and their morphology sets the properties of many metallic alloys. We determine the three-dimensional morphology(More)
We used x-ray nanotomography to characterize the three-dimensional ͑3D͒ morphology and topology of dealloyed nanoporous gold after coarsening. The interface shape distribution obtained from the nanotomography measurement shows that the coarsening does not proceed by bulk diffusion. The surface normal distribution shows that the morphology of the nanoporous(More)
A multi-institutional, multidisciplinary project addresses optimal integration of computational design and efficient experimentation for the accelerated design and development of high performance materials using the example of Nb-based superalloys combining oxidation resistance, creep strength and ductility for aeroturbine applications operating at 1300˚C(More)
First-principles calculations are used to calculate the strain dependencies of the binding and diffusion-activation energies for Ge adatoms on both Si͑001͒ and Ge͑001͒ surfaces. Our calculations reveal that the binding and activation energies on a strained Ge͑001͒ surface increase and decrease, respectively, by 0.21 and 0.12 eV per percent compressive(More)