A Thermodynamic description and phase relationships of the FeCr system: Part II the liquid phase and the fcc phase

The thermodynamic description of the fcc phase in the Al-Cu system has been revised, allowing for the prediction of metastable fcc/liquid phase equilibria to undercoolings of Δ T = 421 K below the eutectic temperature. Hypoeutectic Al-Cu alloys that are prone to pronounced microsegregation were solidified containerlessly in electromagnetic levitation. Solidus and liquidus concentrations were experimentally determined from highly undercooled samples employing energy-dispersive X-ray analysis. Solid concentrations at a rapidly propagating solid/liquid interface were additionally calculated using a sharp interface model that considers all undercoolings and is based on solvability theory. Modelling results (front velocity versus undercooling) were also corroborated by in situ observation with a high-speed camera. A newly established thermodynamic description of the fcc phase in Al-Cu is compatible with existing CALPHAD-type databases. Inconsistencies of previous descriptions such as a miscibility gap between Al-fcc and Cu-fcc on the Al-rich side, an unrealistic curvature of the solidus line in the same composition range or an azeotropic point near the melting point of Cu, are amended in the new description. The procedure to establish the description of phase equilibria at high undercoolings can be transferred to other alloy systems and is of a general nature. This article is part of the theme issue 'Transport phenomena in complex systems (part 2)'.

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Calphad description of the Ge-Mn system

MRS Proceedings ◽

10.1557/opl.2014.444 ◽

2014 ◽

Vol 1642 ◽

Author(s):

Alexandre Berche ◽

Jean-Claude Tédenac ◽

Philippe Jund ◽

Stéphane Gorsse

Keyword(s):

Phase Diagram ◽

Liquid Phase ◽

Thermodynamic Properties ◽

Gibbs Energy ◽

Critical Review ◽

Thermodynamic Description ◽

Calphad Method ◽

Review Of The Literature ◽

Solid Phases

ABSTRACTThe germanium-manganese system has been experimentally studied but no Calphad description is available yet. After a critical review of the literature concerning the phase diagram and the thermodynamic properties, a thermodynamic description of the Gibbs energy of the phases is performed using the Calphad method. The liquid phase is described with an associated model and the variation to the stoichiometry of the solid phases is taken into account.

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Thermodynamics and phase relationships of transition metal-sulfur systems: Part V. A reevaluation of the Fe-S system using an associated solution model for the liquid phase

Metallurgical Transactions B ◽

10.1007/bf02679718 ◽

1985 ◽

Vol 16 (2) ◽

pp. 277-285 ◽

Cited By ~ 48

Author(s):

Y. Y. Chuang ◽

K. C. Hsieh ◽

Y. Austin Chang

Keyword(s):

Liquid Phase ◽

Transition Metal ◽

Solution Model ◽

Associated Solution Model ◽

Associated Solution ◽

Phase Relationships

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A thermodynamic description of data for pure Pb from 0 K using the expanded Einstein model for the solid and the two state model for the liquid phase

Calphad ◽

10.1016/j.calphad.2017.12.008 ◽

2018 ◽

Vol 60 ◽

pp. 144-155 ◽

Cited By ~ 15

Author(s):

A.V. Khvan ◽

A.T. Dinsdale ◽

I.A. Uspenskaya ◽

M. Zhilin ◽

T. Babkina ◽

...

Keyword(s):

Liquid Phase ◽

Thermodynamic Description ◽

State Model ◽

Einstein Model ◽

Two State Model

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Thermodynamic description of the Cu-Ni-Pb system

Open Chemistry ◽

10.2478/s11532-011-0052-4 ◽

2011 ◽

Vol 9 (4) ◽

pp. 743-749 ◽

Cited By ~ 1

Author(s):

Jyrki Miettinen ◽

Vania Gandova ◽

Spas Georgiev ◽

Gueorgui Vassilev

Keyword(s):

Experimental Data ◽

Phase Equilibrium ◽

Liquid Phase ◽

General Solution ◽

Geometric Model ◽

Thermodynamic Description ◽

Experimental Phase ◽

General Solution Model ◽

Experimental Phase Equilibrium ◽

Original Experimental Data

AbstractThermodynamic description is presented for the ternary Cu-Ni-Pb system. Optimized parameters of the sub-systems, Cu-Ni, Cu-Pb and Ni-Pb, are taken from earlier assessments and those of the ternary system are optimized in this study by using the experimental phase equilibrium and thermodynamic data. Better agreement is obtained by the present optimization. Calculated results are compared with the original experimental data to demonstrate the successfulness of this assessment. Moreover, a geometric model (general solution model) is used to estimate ternary integral molar Gibbs excess energies of the liquid phase from the bibary systems only. These values, however, disagree with the quantities obtained by thermodynamic optimizations.

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