Simulation of Fe-Ti-Sb Thernary Phase Diagram at Temperatures above 900 K

Heusler alloys have been considered as one of the most promising thermoelectric materials for electrical power generation in a temperature range of 500–800 °C. Establishment of phase diagrams allows one to predict formation, equilibria, and stability of phases in of these ternary alloys. In this work we report on the simulation and investigation of phase diagram and phase equilibria in ternary Ti-Fe-Sb system which is of considerable interest for thermoelectric applications. The simulation was carried out using the CALPHAD method in Pandat software. The existence of the thermoelectric Heusler TiFe1.5Sb phase was revealed in a temperature range from 970 to 1070 K. The equilibria between TiFe1.5Sb and other phases were determined. The entropy of formation was calculated for the phases existing at 970, 1020 and 1070 K using a fitting approach. A narrow equilibrium region containing pure body centered cubic Fe and TiFe1.5Sb was found.

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Thermodynamic Study of Al-Ge-Sn Ternary Alloys by E.M.F. Measurements

Zeitschrift für Naturforschung A ◽

10.1515/zna-1982-0708 ◽

1982 ◽

Vol 37 (7) ◽

pp. 665-670 ◽

Cited By ~ 3

Author(s):

H. Eslami ◽

M. Gambino ◽

J. P. Bros

Keyword(s):

Phase Diagram ◽

Free Energy ◽

Electrode Potential ◽

Liquidus Surface ◽

Thermodynamic Study ◽

Ternary Alloys ◽

Temperature Range ◽

Partial Free Energy ◽

Potential Study ◽

Mixing Functions

Abstract An electrode potential study of liquid Al-Ge-Sn alloys has been conducted with the cell Al | Al3+ in KCl + LiCl | Al in Al-Ge-Sn in the temperature range 683 K ≦ T ≦ 1273 K. Aluminium partial mixing functions were determined for alloys. These measurements allow us to give the surface corresponding to aluminium partial free energy at 1273 K and the liquidus surface of the Al-Ge-Sn phase diagram.

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Thermodynamic descriptions of the Cu–Zn system

Journal of Materials Research ◽

10.1557/jmr.2008.0035 ◽

2008 ◽

Vol 23 (1) ◽

pp. 258-263 ◽

Cited By ~ 19

Author(s):

Wojciech Gierlotka ◽

Sinn-wen Chen

Keyword(s):

Phase Diagram ◽

Liquid Phase ◽

Thermodynamic Properties ◽

Alloy System ◽

Experimental Information ◽

Calphad Method ◽

Body Centered Cubic ◽

Binary Alloy System ◽

Bcc Phase ◽

Good Agreement

Cu–Zn is an important binary alloy system. In the interested temperature range from 300 to 1500 K, there are eight phases, liquid, Cu, β, β′, γ, δ, ϵ, and Zn phases. The thermodynamic descriptions of the Cu–Zn system are reassessed using the CALPHAD method. A new description of liquid phase and simplified description of body-centered cubic (bcc) phase are proposed. Good agreement has been found among the calculated thermodynamic properties, phase diagram, and the experimental information.

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Phase Diagram of Binary Alloy Nanoparticles under High Pressure

Materials ◽

10.3390/ma14112929 ◽

2021 ◽

Vol 14 (11) ◽

pp. 2929

Author(s):

Han Gyeol Kim ◽

Joonho Lee ◽

Guy Makov

Keyword(s):

Phase Diagram ◽

Phase Diagrams ◽

Interaction Parameter ◽

Excess Volume ◽

Eutectic Temperature ◽

Calphad Method ◽

Alloy Nanoparticles ◽

Thermodynamic Conditions ◽

Nanoparticle System ◽

Pressure Phase

CALPHAD (CALculation of PHAse Diagram) is a useful tool to construct phase diagrams of various materials under different thermodynamic conditions. Researchers have extended the use of the CALPHAD method to nanophase diagrams and pressure phase diagrams. In this study, the phase diagram of an arbitrary A–B nanoparticle system under pressure was investigated. The effects of the interaction parameter and excess volume were investigated with increasing pressure. The eutectic temperature was found to decrease in most cases, except when the interaction parameter in the liquid was zero and that in the solid was positive, while the excess volume parameter of the liquid was positive. Under these conditions, the eutectic temperature increased with increasing pressure.

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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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Experimental Study of Al-Co-Cu Phase Diagram in Temperature Range of 800-1050 °C

Journal of Phase Equilibria and Diffusion ◽

10.1007/s11669-013-0253-y ◽

2013 ◽

Vol 34 (5) ◽

pp. 425-429 ◽

Cited By ~ 1

Author(s):

P. Priputen ◽

T. Y. Liu ◽

I. Černičková ◽

D. Janičkovič ◽

V. Kolesár ◽

...

Keyword(s):

Phase Diagram ◽

Experimental Study ◽

Temperature Range

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The Pressure Dependence of the Phase Diagram t-Butanol/Water

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-0707 ◽

1985 ◽

Vol 40 (7) ◽

pp. 693-698 ◽

Cited By ~ 10

Author(s):

M. Woznyj ◽

H.-D. Lüdemann

Keyword(s):

Phase Diagram ◽

Phase Separation ◽

Liquid Phase ◽

Pressure Dependence ◽

Liquid Phase Separation ◽

Temperature Range ◽

Solid Liquid ◽

Rich Side ◽

Liquid Liquid Phase Separation

The phase diagram t-butanol/water is studied in the temperature range between 200 and 450 K at pressures up to 200 MPa. No liquid/liquid phase separation is observed in this range. The solid/liquid phase diagram reveals the presence of a stable t-butanol/dihydrate at all pressures. At the t-butanol rich side of the diagram solid mixtures with compositions t-butanol/water ~ 5 :1 and ~ 6 : 1 are observed.

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Thermodynamics and Microstructure of Co-V8C7 Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.492-493.523 ◽

2005 ◽

Vol 492-493 ◽

pp. 523-530 ◽

Cited By ~ 2

Author(s):

Shui Gen Huang ◽

Lin Li ◽

Jef Vleugels ◽

Omer Van der Biest

Keyword(s):

Phase Diagram ◽

Vertical Section ◽

Carbon Activity ◽

Calphad Method ◽

Model Parameters ◽

Dsc Analysis ◽

Scanning Calorimetry ◽

Isothermal Sections ◽

Forming Temperature ◽

The Individual

The thermodynamic properties of the Co-V-C and Co-V8C7 systems are of interest for superfine cemented carbide applications. The model parameters for the Gibbs energy of the individual phases have been evaluated using the CALPHAD method by combining the recently optimized phase diagram information of the V-C, Co-C and Co-V system. The isothermal sections of ternary system Co-V-C at 1400 °C and 1600 °C, as well as the vertical section of Co-V8C7 system were extrapolated. The calculated results, especially the liquid forming temperature of Co-V8C7 system was validated with experiments by using differential scanning calorimetry (DSC) analysis. Through controlling the carbon activity, various vertical sections with different carbon activity in Co-V8C7 system are presented.

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Phase diagrams of Ni2+xMn1-xGa Heusler alloys from Hubbard Hamiltonian with account of Jahn-Teller effect

MRS Proceedings ◽

10.1557/opl.2011.633 ◽

2011 ◽

Vol 1310 ◽

Author(s):

Mikhail A. Zagrebin ◽

Vasiliy D. Buchelnikov ◽

Sergey V. Taskaev ◽

Natal’ya Yu. Fedulova

Keyword(s):

Phase Diagram ◽

Free Energy ◽

Phase Transitions ◽

Phase Diagrams ◽

Density Of States ◽

Heusler Alloys ◽

Teller Effect ◽

Hubbard Hamiltonian ◽

Jahn Teller ◽

Jahn Teller Effect

ABSTRACTIn this work a microscopic Hamiltonian is investigated using the Hubbard model for a ferromagnet with two degenerate bands, taking into account the Jahn-Teller effect. A macroscopic free energy is obtained from the microscopic Hubbard Hamiltonian. All free energy coefficients depend on microscopic parameters: temperature T and composition x. As a result of analytical minimization of free energy, phase diagrams are numerically constructed. It is shown that at certain values of parameters on the phase diagrams there are thermodynamic paths which correspond to experimentally observed sequences of phase transitions. Using density of states spectra for different compositions x the T-x phase diagram is numerically constructed. This phase diagram can theoretically explain experimentally observed behavior of the temperatures of phase transitions.

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