Kinetics of Materials - R Balluff S Allen W Carter (Wiley 2005) Episode 15 ppt

... - 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 tensors ... mathematics and physics. Extensive discussion of mechanisms is therefore a feature of this book. We stress rigorous analysis, where possible, and try to build a foundation for un- dersta...

Ngày tải lên: 27/06/2014, 23:20

... 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...

Ngày tải lên: 11/08/2014, 10:22

... 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]. ... Kirkendall effect was observed with inert markers in polymer-solvent systems where the large polymer molecules diffused more slowly than the small solvent molecules [15] . Figure 3.5 s...

Ngày tải lên: 11/08/2014, 10:22

... 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. Similar consider- ations ... 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 str...

Ngày tải lên: 11/08/2014, 10:22

... 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-...

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...

Ngày tải lên: 11/08/2014, 10:22

... 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...

Ngày tải lên: 11/08/2014, 10:22

... 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 e...

Ngày tải lên: 11/08/2014, 10:22

... 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