Kinetics of Materials - R Balluff S Allen W Carter (Wiley 2005) WW Part 3 potx

... 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 ... mobility should 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 relati...

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 ... Kinetics of Materials is the study of the rates at which various processes occur in materials- knowledge of which is fundamental to materials science and engineer- ing....

Ngày tải lên: 11/08/2014, 10:22

... interface curvature; when interfaces possessing regions of different curvatures are present, differences in diffusion poten- tial will drive diffusional transport between these regions in a direction ... 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 f...

Ngày tải lên: 11/08/2014, 10:22

... forces-such as thermal gradients or electric fields- 'Such defects, if present, will be assumed to be in local thermal equilibrium at very small concen- trations. Kinetics of Materials. ... 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-...

Ngày tải lên: 11/08/2014, 10:22

... 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...

Ngày tải lên: 11/08/2014, 10:22

... 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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... 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 illustrated ... isotropic surfaces of larger constant mean curvature to particles of smaller constant mean curvature. This coarsening process and the motion of internal interfaces due to curvature...

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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 ... 3Geometrical constructions for describing anisotropic surfaces are reviewed in Section C .3. 1. Some Geometrical Aspects of Anisotropic Surfaces EXERCISES 35 5 14.2 Assume that self-dif...

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... ss .s Surface Surface Surface diffusion Nondensifying Atoms diffuse along the surface from 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 surface regions to lower-curvature surface regions. VF - - Viscous flow Either Atoms are tr...

Ngày tải lên: 11/08/2014, 10:22

... 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