A micromechanical model of phase boundary movement during solid-solid phase transformations

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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Reactivity in solid phase. Transformations of 2,4-di-tert-butylphenol and its derivatives under elastic deformation conditions

Russian Chemical Bulletin ◽

10.1007/bf01434226 ◽

1996 ◽

Vol 45 (6) ◽

pp. 1428-1432

Author(s):

V. B. Vol'eva ◽

I. S. Belostotskaya ◽

A. Yu. Karmilov ◽

N. L. Komissaroya ◽

V. V. Ershov

Keyword(s):

Phase Transformations ◽

Elastic Deformation ◽

Solid Phase

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Reactive Diffusion at the Cylindrical Dissolving of Copper in the Solder Melt

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.312-315.387 ◽

2011 ◽

Vol 312-315 ◽

pp. 387-392 ◽

Cited By ~ 1

Author(s):

Jaromír Drápala ◽

Alena Struhařová ◽

Daniel Petlák ◽

Vlastimil Vodárek ◽

Petr Kubíček

Keyword(s):

Time Course ◽

Solid Phase ◽

Accurate Determination ◽

Theoretical Description ◽

Reactive Diffusion ◽

Interface Boundary ◽

Boundary Movement ◽

Long Time ◽

Melt Cooling

Problems of reactive diffusion at the solid phase and melt contact were studied theoretically and experimentally. The main intention was to calculate the time course of the solid phase dissolving in the case of cylindrical dissolving. These calculations were carried out on the assumption for the rate constant of dissolving K = const. In our work we give heed especially to the dominating process, which is the solid metal A dissolved in the melt B. During the dissolving the melt B saturates with the metal A and the process is influenced by convections which are characteristic for the given experimental configuration. A theoretical description of the kinetics of the solid phase dissolving in the melt will be presented for the case of cylindrical dissolving. The aim is to derive a relation for the interface boundary movement c(t) in dependence on time and a time course of growth of the element A concentration in the melt B. There are problems with accurate determination of the interface boundary movement after certain heating times of specimens, when it is observed experimentally, since intermetallic phases create in the original A metal at both the diffusion and cooling and some phases segregate at the solidifying melt cooling. The main intention was an experimental study of the copper dissolving in the tin melt. Experiments aimed to the determination of the Cu wires (diameters from 0.5 to 3.5 mm) dissolution in the solder melt were carried out at various selected temperatures and times. Rapid growth of phases in the metal A and determination of the thickness of layers with these phases pose considerable time demands to X-ray micro-analyses (WDX, EDX) of specimens after their long-time heating.

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

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

10.1098/rspa.1981.0156 ◽

1981 ◽

Vol 378 (1774) ◽

pp. 351-368 ◽

Cited By ~ 42

Keyword(s):

Phase Transformations ◽

Volume Diffusion ◽

Solid Phase ◽

Parent Phase ◽

Steady Motion ◽

Diffusion Field ◽

Lateral Growth ◽

Small Perturbations ◽

Step Motion ◽

Kinetics Of

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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Multiphase Phase-Field Approach for Virtual Melting: A Brief Review

Material Science Research India ◽

10.13005/msri/180201 ◽

2021 ◽

Vol 18 (2) ◽

pp. 102-107

Author(s):

Arunabha Mohan Roy

Keyword(s):

Phase Transformations ◽

Phase Field ◽

Field Model ◽

Solid Phase ◽

Scale Effects ◽

Phase Field Model ◽

Short Review ◽

Nanoscale Material ◽

Material Parameters ◽

Field Approach

A short review on a thermodynamically consistent multiphase phase-field approach for virtual melting has been presented. The important outcomes of solid-solid phase transformations via intermediate melt have been discussed for HMX crystal. It is found out that two nanoscale material parameters and solid-melt barrier term in the phase-field model significantly affect the mechanism of PTs, induces nontrivial scale effects, and changes PTs behaviors at the nanoscale during virtual melting.

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