Kinetics of isothermal phase transformations above and below the peritectic temperature: Phase-field simulations

We present phase-field simulations of isothermal phase transformations in the peritectic system below and above the peritectic temperature TP , and in the monotectic system below the monotectic temperature TM. We focus particularly on the Liquid-Film-Migration (LFM) mechanism, which appears to be the generic process for phase transformations above TP . Below TP , we obtain an assymetric LFM, suggesting the existence of a doublon structure in free space. In the monotectic system, the transformation from a liquid L1 to a solid+liquid L2 mixture proceeds via the migration of a L2 film, which is the analogous of the LFM process. When the metastable state consists of a liquid-liquid mixture, a dendritic-like solidification is obtained.

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In situ impedance spectroscopy on pyrophyllite and CaCO3 at high pressure and temperature: phase transformations and kinetics of atomistic transport

Physics and Chemistry of Minerals ◽

10.1007/s00269-007-0162-x ◽

2007 ◽

Vol 34 (7) ◽

pp. 445-465 ◽

Cited By ~ 10

Author(s):

J. H. Ter Heege ◽

J. Renner

Keyword(s):

High Pressure ◽

Impedance Spectroscopy ◽

Phase Transformations ◽

Temperature Phase ◽

High Pressure And Temperature ◽

Kinetics Of

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Prediction of the kinetics of the phase transformations and the associated microstructure during continuous coolingin the Ti17

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:2004120010 ◽

2004 ◽

Vol 120 ◽

pp. 93-101

Author(s):

J. Da Costa Teixeira ◽

L. Héricher ◽

B. Appolaire ◽

E. Aeby-Gautier ◽

G. Cailletaud ◽

...

Keyword(s):

Electrical Resistivity ◽

Phase Transformation ◽

Phase Transformations ◽

Phase Field ◽

Experimental Results ◽

Thermal Treatments ◽

Thermal Gradients ◽

Resistivity Measurements ◽

Isothermal Conditions ◽

Kinetics Of

The aim of this paper is to present recent experimental results and related simulation about the β → αGB + αWGB and → αWI transformations which occur in the Ti17 alloy during the thermal treatments following the heating in the β phase field. These phase transformations were experimentally studied under isothermal conditions in samples with negligible thermal gradients. The IT diagram was obtained, on the basis of electrical resistivity measurements and microstructural SEM observations. The kinetics of the phase transformation was further numerically simulated for continuous cooling on the basis of a formerly developed model giving the amount of each morphology (αWGB, αWI). Experimental and calculated results are compared.

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Thermomechanical States in Arc Weld Surfaced Steel Elements

Archives of Metallurgy and Materials ◽

10.1515/amm-2016-0264 ◽

2016 ◽

Vol 61 (3) ◽

pp. 1623-1634 ◽

Cited By ~ 5

Author(s):

J. Winczek ◽

T. Skrzypczak

Keyword(s):

Phase Transformations ◽

Cross Section ◽

Plastic State ◽

Temperature Phase ◽

Field Phase ◽

Stress Equilibrium ◽

Austenitic Transformation ◽

Transformation Stress ◽

Kinetics Of ◽

Made In

AbstractThe paper presents a model of temperature, phase transformation and stresses fields in a steel element during single-pass Gas Metal Arc Weld (GMAW) surfacing.Kinetics of phase transformations during heating is limited by temperature values at the beginning and at the end of austenitic transformation, while the progress of phase transformations during cooling is determined on the basis of TTT-welding diagram and Johnson-Mehl-Avrami and Kolomogorov law for diffusive transformations and Koistinen-Marburger for martensitic transformation. Stress state of a bar subjected to thermo-mechanical loads is described assuming the plane cross section hypothesis and using integral equations of stress equilibrium of a bar as well as simple Hook’s law. Stresses in the elastic-plastic state are determined by iteration using solutions with a variable elastic modulus of elasticity, conditioned by tensile curves. Dependence of stresses on strains is assumed on the basis of tensile curves of particular structures, taking into account the influence of temperature. There were performed calculations of the temperature field, phase transformations, strains and stresses for GMAW surfacing of a cuboid element made of S235 steel. Authors’ programs, made in Borland Delphi, were used for calculations.

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