Kinetics of Materials - R Balluff S Allen W Carter (Wiley 2005) WW Part 11 pptx

... larger-curvature surface regions to lower- curvature surface regions. ss.v Surface Surface Vapor transport Nondensifying Atoms are transported through the vapor phase from larger-curvature ... process is called Coble creep. Grain boundaries serve as both sources and sinks in polycrystalline materials- those grain boundaries with larger normal tensile loads are sinks for atoms trans- ....

Ngày tải lên: 11/08/2014, 10:22

... CONTENTS 12.2 Motion of Crystal/Vapor Interfaces 12.2.1 Structure of Crystal/Vapor Surfaces 12.2.2 Crystal Growth from a Supersaturated Vapor 12.2.3 Surfaces as Sinks for Supersaturated Lattice ... - Anew-rOld new old-rnew This pattern-a rank-one tensor is transformed by a single matrix multiplication and a rank-two tensor is transformed by two matrix multiplications-holds for...

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... follow from statements of the first and second laws of thermodynamics. Onsager s principle supplements these postulates and follows from the statisti- cal theory of reversible fluctuations [5]. ... therefore demonstrates the role of microscopic reversibility in the symmetry of the Onsager coefficients. More demonstrations of the Onsager principle are described in Lifshitz...

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... distortions in the fixed stress field, so different amounts of work, W, must be done against the stress field during these jumps. The rate of a particular jump in the absence of stress is proportional ... vary linearly with stress and be expressible as a tensor in the very general linear form (3.78) kl where the stress-dependent terms in the sum are relatively small. Simila...

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... ENT SYSTEMS In earlier chapters we examined systems with one or two types of diffusing chem- ical species. For binary solutions, a single interdiffusivity, 5, suffices to describe composition ... everywhere except where its argument is zero, where it has an infinite singularity. It has the property s j(F')6(F- Fo)dr'= f (r& apos;0); so it also follows that s6 (F-...

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... the ratio of strain over stress) is then El .E2 - 1- -_ - (~1 - 2~2) eiWt S( W) = uo eiWt uo go (8.71) Because the strain lags behind the stress, the stress-strain curve for each ... mechanical response of anelastic materials. Scalar forces in the spring and dashpot model become analogs for a more complex stress tensor in materials. To enforce this an...

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... diffusion on most surfaces is anisotropic because of their low two-dimensional symmetry. When the surface structure consists of parallel rows of closely spaced atoms, separated by somewhat larger ... somewhat larger inter-row distances, diffusion is usually easier parallel to the dense rows than across them. In some cases, it appears that the 60ur discussion follows reviews by...

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... mean curvature. Such capillary forces are especially influential in fine-scale microstructures containing interfaces with large curvatures where pressure differ- ences can become correspondingly ... boundary with isotropic surface energy yB intersects a free surface with isotropic surface energy ysl a grain-boundary groove forms in order to achieve a capillary-force balance, as illu...

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... the grain center. The pressure due to this curvature therefore induces growth. Grains with fewer than six sides show the opposite behavior, whereas grains with six sides possess flat sides and ... Number of sides (a) (b) Figure 15.14: (a) Average area of grains vs. time. (b) Fraction of grains possessing N sides. Figures compare Marder&apos ;s theoretical results with ex...

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... the case of phase transformations) is absent and the interface s core structure consists of all “bad material.” It is generally assumed that any shear stresses applied across such an interface ... Clusters. As described in Section B.l, for incoherent interfaces all of the lattice registry characteristic of the reference structure (usually taken as the crystal structure of...

Ngày tải lên: 11/08/2014, 10:22