Kinetics of Materials - R Balluff S Allen W Carter (Wiley 2005) WW Part 2 ppt

... 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]. ... balance of forward and backward rates is characteristic of the equilibrium state, and detailed balance exists throughout the system. Microscopic reversibility therefore requires...

Ngày tải lên: 11/08/2014, 10:22

... Analysis of such diffusion is complex because multiple cross terms and particle- particle chemical interaction terms appear. The cross terms result in N2 indepen- dent interdiffusivities for ... 2. 2 .2. EXERCISES 129 where q = @, Using standard tables of transforms to transform back to (2, t) coordinates, the final solutions are Because erf(z) = -erf(-z), the solutio...

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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 a...

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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 ... of grains possessing N sides. Figures compare Marder&apos ;s theoretical results with experimental measurements of bubble growth in soap froths made by Glazier et al. From Marder [25...

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... 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. ... polycrystalline materials- those grain boundaries with larger normal tensile loads are sinks for atoms trans- ported from grain boundaries under lower tensile loads and from those under...

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... association with growth spirals on surfaces, 29 1 climb of, 26 6 379, 478 Bardeen-Herring source/sink for climb force due to stress, 25 5 diffusion-limited kinetics, 26 7 dislocations as sinks for ... vs. djscontinuous free-energy changes during, 428 Landau expansion of free energy, 420 order of a phase transformation, 420 order parameters, 420 conserved vs. non-cons...

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... Bibliography Exercises 22 2 22 3 22 4 22 5 10 Diffusion in Noncrystalline Materials 22 9 10.1 Free-Volume Model for Liquids 22 9 10 .2 Diffusion in Amorphous Metals 23 2 10 .2. 1 Self-Diffusion 23 2 ... from a Supersaturated Vapor 12. 2.3 Surfaces as Sinks for Supersaturated Lattice Vacancies 12. 3.1 Structure of Crystal/Liquid Interfaces 12. 3 .2 Crystal Growth fro...

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... {fir(Rz -r2 )sin8+fie [ (R2 +r2 )cose+2Rr]} (3.109) The force on an interstitial lying on a cylinder of radius R centered on the origin where [RZ + r2 + 2Rr cos el2 r = R is then ... absence of stress is proportional to the exponential factor exp[-Gm/(lcT)], where G" is the free-energy barrier to the 16When the stress is nonuniform and stress gradients exist,...

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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...

Ngày tải lên: 11/08/2014, 10:22