The growth kinetics of individual ledges during solid-solid phase transformations

The problem of step motion during lateral growth in solid-solid phase transformations is re-examined. Results are obtained for the steady motion of an individual ledge when volume diffusion in the parent phase is the predominant contribution to the growth rate. A comparison is made between our results and the earlier work of Jones & Trivedi (1971). There are significant differences between the two sets of results particularly in the limit of small perturbations to the Laplacian diffusion field. To confirm the accuracy of the results presented here the calculations have been made by two different methods.

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The growth kinetics of ledges during phase transformations: multistep interactions

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1982.0150 ◽

1982 ◽

Vol 384 (1786) ◽

pp. 107-133 ◽

Cited By ~ 32

Keyword(s):

Steady State ◽

Phase Transformations ◽

Growth Kinetics ◽

Volume Diffusion ◽

Asymptotic Methods ◽

Parent Phase ◽

Growth Characteristics ◽

Controlling Factor ◽

Kinetics Of ◽

Equal Height

An analysis of the growth characteristics of a train of ledges is presented, where volume diffusion in the parent phase is assumed to be the rate- controlling factor. First a train of steps of unequal height is considered where the step heights are assumed to be consistent with a steady-state motion so that each step moves with the same speed. It is possible to analyse this situation by asymptotic methods when the steps are either far apart or close together. Explicit results are given for both two- and three-step trains and it is shown how the step heights must vary if a given train is to move steadily at a specified speed. Trains of steps of equal height are also considered and an analysis is made of the relative velocities of such steps due to their interaction.

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Mesoscale simulations of the kinetics of solid–solid phase transformations: Selecting the relevant interfacial compositions for shape-preserved growth

Comptes Rendus Physique ◽

10.1016/j.crhy.2010.07.006 ◽

2010 ◽

Vol 11 (3-4) ◽

pp. 257-264 ◽

Cited By ~ 1

Author(s):

Christopher R. Hutchinson ◽

Hatem S. Zurob

Keyword(s):

Phase Transformations ◽

Solid Phase ◽

Kinetics Of ◽

Mesoscale Simulations

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The influence of concentration-dependent diffusivity on the growth kinetics of individual ledges during solid–solid phase transformations

Acta Materialia ◽

10.1016/j.actamat.2006.11.044 ◽

2007 ◽

Vol 55 (7) ◽

pp. 2503-2508 ◽

Cited By ~ 1

Author(s):

C. Atkinson

Keyword(s):

Phase Transformations ◽

Growth Kinetics ◽

Solid Phase ◽

Kinetics Of ◽

Concentration Dependent Diffusivity

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Lateral Growth in Solid‐Solid Phase Transformations

Journal of Applied Physics ◽

10.1063/1.1659770 ◽

1971 ◽

Vol 42 (11) ◽

pp. 4299-4304 ◽

Cited By ~ 123

Author(s):

G. J. Jones ◽

R. K. Trivedi

Keyword(s):

Phase Transformations ◽

Solid Phase ◽

Lateral Growth

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Effect of particle size distribution on the kinetics of solid phase-gas reactions

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19751119 ◽

1975 ◽

Vol 40 (4) ◽

pp. 1119-1125 ◽

Cited By ~ 2

Author(s):

J. Skřivánek ◽

J. Šubrt

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Size Distribution ◽

Solid Phase ◽

Effect Of Particle Size ◽

Gas Reactions ◽

Kinetics Of

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Heat capacities and enthalpies of fusion and transformation for solvates of some salts with dimethyl sulfoxide and dimethylformamide

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19883072 ◽

1988 ◽

Vol 53 (12) ◽

pp. 3072-3079

Author(s):

Mojmír Skokánek ◽

Ivo Sláma

Keyword(s):

Heat Capacity ◽

Phase Transformation ◽

Phase Transformations ◽

Dimethyl Sulfoxide ◽

Liquidus Temperature ◽

Molar Heat Capacity ◽

Solid Phase ◽

Zinc Nitrate ◽

Heat Capacities ◽

Liquid Phases

Molar heat capacities and molar enthalpies of fusion of the solvates Zn(NO3)2 . 2·24 DMSO, Zn(NO3)2 . 8·11 DMSO, Zn(NO3)2 . 6 DMSO, NaNO3 . 2·85 DMSO, and AgNO3 . DMF, where DMSO is dimethyl sulfoxide and DMF is dimethylformamide, have been determined over the temperature range 240 to 400 K. Endothermic peaks found for the zinc nitrate solvates below the liquidus temperature have been ascribed to solid phase transformations. The molar enthalpies of the solid phase transformations are close to 5 kJ mol-1 for all zinc nitrate solvates investigated. The dependence of the molar heat capacity on the temperature outside the phase transformation region can be described by a linear equation for both the solid and liquid phases.

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A Study of the Impact of Graphite on the Kinetics of SPS in Nano- and Submicron WC-10%Co Powder Compositions

Ceramics ◽

10.3390/ceramics4020025 ◽

2021 ◽

Vol 4 (2) ◽

pp. 331-363

Author(s):

Eugeniy Lantcev ◽

Aleksey Nokhrin ◽

Nataliya Malekhonova ◽

Maksim Boldin ◽

Vladimir Chuvil'deev ◽

...

Keyword(s):

Activation Energy ◽

Solid Phase ◽

Continuous Heating ◽

Diffusion Creep ◽

Hard Alloys ◽

Fine Grained ◽

Plasma Sintering ◽

Spark Plasma ◽

The Impact ◽

Kinetics Of

This study investigates the impact of carbon on the kinetics of the spark plasma sintering (SPS) of nano- and submicron powders WC-10wt.%Co. Carbon, in the form of graphite, was introduced into powders by mixing. The activation energy of solid-phase sintering was determined for the conditions of isothermal and continuous heating. It has been demonstrated that increasing the carbon content leads to a decrease in the fraction of η-phase particles and a shift of the shrinkage curve towards lower heating temperatures. It has been established that increasing the graphite content in nano- and submicron powders has no significant effect on the SPS activation energy for “mid-range” heating temperatures, QS(I). The value of QS(I) is close to the activation energy of grain-boundary diffusion in cobalt. It has been demonstrated that increasing the content of graphite leads to a significant decrease in the SPS activation energy, QS(II), for “higher-range” heating temperatures due to lower concentration of tungsten atoms in cobalt-based γ-phase. It has been established that the sintering kinetics of fine-grained WC-Co hard alloys is limited by the intensity of diffusion creep of cobalt (Coble creep).

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Effect of maturity of Napier grass (Pennisetum purpureum) hay on intake, digestibility, and rumen dynamics when given to zebu bulls

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200001459 ◽

2000 ◽

Vol 2000 ◽

pp. 144-144

Author(s):

A.J. Ayala-Burgos ◽

F.D.DeB. Hovell ◽

R.M. Godoy ◽

Hamana S. Saidén ◽

R. López ◽

...

Keyword(s):

Liquid Phase ◽

Solid Phase ◽

Napier Grass ◽

Pennisetum Purpureum ◽

Ad Libitum ◽

The Tropics ◽

Kinetics Of

Cattle in the tropics mostly depend on pastures. During dry periods the forage available is usually mature, constraining both intake and digestion. These constraints need to be understood, for intake and digestibility define productivity. Intake depends on the rumen space made available by fermentation and outflow. Markers such as PEG (liquid phase), and chromium mordanted fibre (solid phase) can be used to measure rumen volume and outflow, but have limitations. The objective of this experiment was to measure intake, digestibility, and rumen kinetics of cattle fed ad libitum forages with very different degradation characteristics, and also to compare rumen volumes measured with markers with those obtained by manual emptying.

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