scholarly journals Calculation of the thermodynamic properties of the Ga-Sb-Tl liquid alloys

2005 ◽  
Vol 70 (1) ◽  
pp. 9-20 ◽  
Author(s):  
Dragan Manasijevic ◽  
Dragana Zivkovic ◽  
Katayama Iwao ◽  
Zivan Zivkovic
Keyword(s):  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Ternary System ◽  
Thermodynamic Model ◽  
Excess Gibbs Energy ◽  
Similarity Coefficient ◽  
Thermodynamic Calculations ◽  
Liquid Alloys ◽  
Geometric Models ◽  
Good Agreement

The results of the calculation of the thermodynamic properties for liquid Ga-Sb-Tl alloys at the temperature 1073 K are presented in this paper. Initially, the most appropriate thermodynamic model for the investigated system was selected. Based on a comparison of the values calculated by different geometric models (Kohler, Muggianu, Toop, Hillert, Chou) with the existing experimental based data, asymmetric models of calculation were determined to give the best results. The asymmetric nature of the investigated ternary system was additionally confirmed by the Chou similarity coefficient concept. For these reasons, further complete thermodynamic calculations were performed according to the Hillert model in five sections of the ternary Ga-Sb-Tl system from each corner with the mole ratio of other two components being 9:1; 7:3; 5:5; 3:7 and 1:9. The obtained results include integral excess Gibbs energy dependences on composition for all the investigated sections. The calculated activity values at 1073 K for all components are given in the form of isoactivity diagrams. Comparison between the calculated and experimentally obtained gallium activities shows good agreement.

scholarly journals MODELING OF THERMODYNAMIC PROPERTIES OF THE MELTS OF TERNARY Ge-Mn-Gd SYSTEM

2019 ◽  
pp. 18-22
Author(s):  
N. Golovata ◽  
N. Kotova ◽  
N. Usenko
Keyword(s):  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Ternary System ◽  
Binary Systems ◽  
Thermodynamic Characteristics ◽  
Published Data ◽  
Liquid Alloys ◽  
Model Calculations ◽  
Enthalpies Of Mixing ◽  
Gibbs Energies

In the present work, the Gibbs energies of mixing of liquid alloys of the Ge-Mn-Gd ternary system were determined, which was made on the basis of an analysis of published data on the thermodynamic properties of liquid alloys of boundary binary systems that form the ternary Ge-Mn-Gd, as well as on the basis of the model calculations in these binary systems. To determine the activities of the components, the Gibbs energies of mixing, and the enthalpies of mixing of liquid alloys of the Ge-Mn(Gd) systems, for which alloying process is accompanied by significant heat release, an ideal associated solution model was applied. For the melts of the Mn-Gd system, which are characterized by rather insignificant exothermic effects, a model of regular solutions was used. The surface of the Gibbs energy of mixing for the alloys of the Ge-Mn-Gd ternary system has been determined on the basis of the concentration dependences of the Gibbs energies of mixing obtained for constituent binary systems under the assumption of additivity of pair interactions using the Redlich-Kister-Muggianu method. The obtained topology of the Gibbs energy isolines projections is compared with the thermochemical properties of liquid alloys of this system that we have determined earlier. A comparative analysis of the topology of these surfaces in the Ge-Mn-Gd system led to the conclusion that the surfaces of ΔG and ΔmH monotonically decrease from the manganese-rich angle of the diagram towards the Ge-Gd side of the concentration triangle. The minimum value of the thermodynamic characteristics of mixing of the ternary liquid alloys corresponds to the composition, which coincides with the composition of the most stable intermetallic compound in the Ge-Gd system. From the course of isolines of free energies and integral enthalpies of mixing, one can also conclude about the influence of a short-range order, existed in the Ge-Mn system near the composition with a mole fraction of mangan greater than 0.7, on the properties of ternary alloys in the vicinity of this composition. Thus, the topology of isolines and the large exothermic values of the obtained thermodynamic properties allow us to make a reasonable conclusion that the strong interaction between unlike components inherent in the Ge-Gd system in the solid state is also maintained for liquid alloys of the Ge-Mn-Gd system.

Extension of a lattice model of electrolytes to a ternary system of a salt and two solvents. The system CH3OH-H2O-LiCl

1989 ◽  
Vol 54 (6) ◽  
pp. 1464-1474
Author(s):  
Ivan Horsák
Keyword(s):  
Experimental Data ◽  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Ternary System ◽  
Lattice Model ◽  
Excess Gibbs Energy ◽  
Binary Data ◽  
Ternary Systems ◽  
Electrolyte Solutions ◽  
Ternary Contribution

A lattice model proposed to describe the thermodynamic properties of binary electrolyte solutions over the whole concentration range has been extended to ternary systems involving two solvents. The relationships derived for the excess Gibbs energy and the activity coefficients of all the components have been tested with published experimental data on vapour pressures of methanol and water in the system CH3OH-H2O-LiCl at 60 °C. Examination of the ability of the model to predict the behaviour of the ternary system on the basis of binary data has shown that the expression for the excess Gibbs energy must be extended to include a ternary contribution.

scholarly journals Thermodynamic investigation of liquid properties of the Ni–Sn–Ti ternary system using CALPHAD method and geometric models

2016 ◽  
Vol 1 (4) ◽  
pp. 14
Author(s):  
Vanya Gandova
Keyword(s):  
Liquid Phase ◽  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Excess Gibbs Energy ◽  
Geometric Model ◽  
Calphad Method ◽  
Geometric Models ◽  
Molar Excess Gibbs Energy ◽  
Molar Excess ◽  
Ternary Parameters

Predictions for the liquid Ni–Sn–Ti alloys thermodynamic properties (molar excess Gibbs energy) are presented. The calculations were performed in the temperature range 1000–2000 K.  Geometric models (using data from the binary end-systems) were used and the respective calculated molar excess Gibbs energy values were compared to CALPHAD method assessments. The concentration dependences of the liquid phase thermodynamic properties along different vertical sections Sn:Ti, Ni:Ti and Ni:Sn were estimated.Ternary interaction parameters (L0, L1 and L2) of the liquid phase were determined using General solution (geometric) model from thermodynamic data of the binary end–systems (Ni–Sn, Ni–Ti, Sn–Ti).  Ternary parameters exhibit values: L0 = - 70360.5 - 0.263*T; L1 = -113023 - 11.574*T; L2 = - 131755 - 17.101*T. Negative molar excess Gibbs energies were obtained by all models.

Evaluation of the Thermodynamic Properties and Phase Equilibria of the Ordered γ’ and Disordered γ Phases in the Ni-Al-Ta System

2002 ◽  
Vol 755 ◽  
Author(s):  
Shihuai Zhou ◽  
Long-Qing Chen ◽  
Rebecca A. MacKay ◽  
Zi-Kui Li u
Keyword(s):  
Experimental Data ◽  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Phase Equilibria ◽  
Phase Diagrams ◽  
Gibbs Energy Function ◽  
Ternary Interaction ◽  
Two Phases ◽  
Rich Side ◽  
Good Agreement

ABSTRACTThe phase equilibria and thermodynamic properties of the ternary Ni-Al-Ta system on Ni-rich side were analyzed. Thermodynamic descriptions of the liquid, γ-fcc, γ'-L12, and π-Ni6AlTa phases were obtained using the CALPHAD (CALculation of PHase Diagrams) technique. The thermodynamics of γ-fcc and γ'-L12 phases were modeled with a single Gibbs energy function taking into account the crystallographic relation between the two phases. The ternary interaction parameters of the liquid and fcc phases were also determined. The calculated phase diagrams of the ternary Ni-Al-Ta system show a good agreement with experimental data.

Evaluation of Wagner Interaction Parameter in Fe-Mn-Si-Nb-Ti-V-C System

2005 ◽  
Vol 475-479 ◽  
pp. 3327-3330 ◽  
Author(s):  
Sang Hwan Lee ◽  
Kyung Sub Lee ◽  
Kyung Jong Lee
Keyword(s):  
Gibbs Energy ◽  
Thermodynamic Model ◽  
Lattice Model ◽  
Excess Gibbs Energy ◽  
Chemical Potential ◽  
Solution Model ◽  
Interaction Parameters ◽  
Dilute Solution ◽  
Relationship Of ◽  
The Relationship

The dilute solution model is quite widely used because the chemical potential is more easily defined than that in the sub-lattice model. In the present study, the thermodynamic model for the Fe-Mn-Si-Nb-Ti-V-C system was conducted by evaluating Wagner interaction parameters. The data used in this work was collected and modified by means of TCFE 2000-database in Thermo-Calc and up-to date references. The relationship of interaction parameters(L) in the sub-lattice model and Wagner interaction parameters in the dilute solution model was derived. The composition dependency of reference state and the higher order interaction parameters of the excess Gibbs energy were considered to evaluate Wagner interaction parameters. The equilibrium compositions of austenite and fractions of phases and the dissolution temperature of precipitates(NbC, VC, and TiC) were evaluated by the dilute solution model and compared with the results by the sub-lattice model.

scholarly journals A Theoretical study of thermodynamic properties of Cd-Bi liquid alloy

BIBECHANA ◽  
1970 ◽  
Vol 8 ◽  
pp. 90-95
Author(s):  
D Adhikari
Keyword(s):  
Free Energy ◽  
Thermodynamic Properties ◽  
Liquid Alloy ◽  
Theoretical Study ◽  
Energy Parameter ◽  
Heat Of Mixing ◽  
Liquid Alloys ◽  
Energy Of Mixing ◽  
Free Energy Of Mixing ◽  
Good Agreement

Flory’s model has been used for the study of thermodynamic properties of Cd-Bi liquid alloys. Free energy of mixing, heat of mixing, entropy of mixing and activity of Cd have been determined. All of these computed quantities have been found to be in a good agreement with observed values.Keywords: Flory’s model; thermodynamic properties; Cd-Bi liquid alloy; weakly interacting system; interaction energy parameter  DOI: http://dx.doi.org/10.3126/bibechana.v8i0.5693  BIBECHANA 8 (2012) 90-95

scholarly journals Modelling thermodynamic properties of binary Cu–Eu and ternary Al–Cu–Eu melts

2020 ◽  
Vol 8 (2) ◽  
pp. 73-82
Author(s):  
Natalia Kotova ◽  
Natalia Golovata ◽  
Natalia Usenko
Keyword(s):  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Excess Gibbs Energy ◽  
Model Calculations ◽  
Gibbs Energies ◽  
Excess Gibbs Energies ◽  
Energy Of Mixing ◽  
Gibbs Energy Of Mixing ◽  
Associated Solution Model ◽  
Associated Solution

Model calculations of the whole set of thermodynamic properties of liquid alloys for the binary Cu–Eu and ternary Al–Cu–Eu systems have been performed. Authors used the ideal associated solution model (IAS model) for calculation of the entropies and excess Gibbs energies of mixing for these systems. The binaries were given as the Redlich-Kister polynomials. The thermodynamic properties for the ternary system are described using the Redlich-Kister-Muggianu formalism. A comparison of the surfaces of excess Gibbs energy and entropy of mixing for liquid Al–Cu–Eu alloys at 1350 K demonstrates that the ordering related to the formation of rather strong associates in the Al–Eu system significantly affects the concentration dependence of the excess Gibbs energy of mixing in the liquid phase at this temperature.

scholarly journals Thermodynamic modeling of the Fe−Zn system using exponential temperature dependence for the excess Gibbs energy

2011 ◽  
Vol 47 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Y. Tang ◽  
X. Yuan ◽  
Y. Du ◽  
W. Xiong
Keyword(s):  
Experimental Data ◽  
Liquid Phase ◽  
Binary System ◽  
Thermodynamic Properties ◽  
Gibbs Energy ◽  
Excess Gibbs Energy ◽  
Miscibility Gap ◽  
Exponential Equation ◽  
Self Consistent ◽  
Exponential Temperature Dependence

The Fe-Zn binary system was re?modeled using exponential equation Li=hi?exp(-T/?i) (i=0,1,2?) to describe the excess Gibbs energy of the solution phases and intermetallic compounds with large homogeneities. A self-consistent set of thermodynamic parameters is obtained and the calculated phase diagrams and thermodynamic properties using the exponential equation agree well with the experimental data. Compared with previous assessments using the linear equation to describe the interaction parameters, the artificial miscibility gap at high temperatures was removed. In addition, the calculated thermodynamic properties of the liquid phase were more reasonable than those resulting from all the previous calculations. The present calculations yield noticeable improvements to the previous calculations.

scholarly journals Thermodynamic calculations in ternary titanium-aluminium-manganese system

2008 ◽  
Vol 73 (4) ◽  
pp. 499-506 ◽  
Author(s):  
Ana Kostov ◽  
Dragana Zivkovic
Keyword(s):  
Experimental Data ◽  
Thermodynamic Properties ◽  
Ternary System ◽  
Thermodynamic Analysis ◽  
Experimental Results ◽  
Thermodynamic Calculations ◽  
Thermodynamic Optimization ◽  
Gibbs Energies ◽  
Different Temperatures ◽  
Titanium Aluminium

Thermodynamic calculations in the ternary Ti-Al-Mn system are shown in this paper. The thermodynamic calculations were performed using the FactSage thermochemical software and database, with the aim of determining thermodynamic properties, such as activities, coefficient of activities, partial and integral values of the enthalpies and Gibbs energies of mixing and excess energies at two different temperatures: 2000 and 2100 K. Bearing in mind that no experimental data for the Ti-Al-Mn ternary system have been obtained or reported. The obtained results represent a good base for further thermodynamic analysis and may be useful as a comparison with some future critical experimental results and thermodynamic optimization of this system.

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