Kinetics of Materials - R Balluff S Allen W Carter (Wiley 2005) WW Part 1 pot

... inverse transformations, Aold-+newAnew-old +new - J;ew + = Aold-+new old new-old*ew - - J4 - - XA - - A and (1. 31) Anew-Old old-newJ’old - - J’old - - Anew-oldXnewAold-new*ld ... Kinetics of Materials is the study of the rates at which various processes occur in materials- knowledge of which is fundamental to materials sci...

Ngày tải lên: 11/08/2014, 10:22

... absence of stress is proportional to the exponential factor exp[-Gm/(lcT)], where G" is the free-energy barrier to the 16 When the stress is nonuniform and stress gradients exist, the stress will ... 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 consi...

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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 ... 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 of Shew...

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]. ... 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

... 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-...

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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...

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... external macroscopic shape and its in- ternal microstructure-when suitable driving forces exist. As always, these driving forces result from differential decreases in total free energy. Morphology ... Physics of Powder Metallurgy, pages 14 3 -1 79, New York, 19 51. McGraw-Hill. W. T. Read. Dislocations in Crystals. McGraw-Hill, New York, 19 53. H. Gleiter. The mechanism o...

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... grain-boundary free energy decreases. This process is also competitive and often produces unwanted coarse-grained structures. 15 .1 COARSENING OF A DISTRIBUTION OF PARTICLES 15 .1. 1 In 19 61, ... 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 si...

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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. ... quadjunctions (as in Sections 16 .1. 1 and 16 .1. 2), the process is called Coble creep. Grain boundaries serve as both sources and sinks in polycrystalline materials- those grain bo...

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... the reference structure (usually taken as the crystal structure of the matrix in the case of phase transformations) is absent and the interface s core structure consists of all “bad material.” ... problems of this type, the quantities that are given are the inclusion shape, the stress-free transformation strains E;, the elastic properties of the two phases, and the degree...

Ngày tải lên: 11/08/2014, 10:22