A new self-consistent model for thermodynamics of binary solutions

Svoboda, Jiřı́; Shan, Yao V.; Fischer, Franz Dieter

doi:10.1016/j.scriptamat.2015.06.014

Cited by 4 publications

(5 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With this formulation, we have improved the configurational entropy of a system with couples and pairs, compared to previous formulations in the literature, see also [18,19].…”

Section: Determination Of Configurational Entropymentioning

confidence: 94%

“…In reality, however, the equilibrium numbers of Cs and Ps do depend on interaction energies between atoms of individual solutes and of the solvent. Here we refer to two recent contributions by Svoboda and Fischer, which introduced a so-called self-consistent model for binary systems and later for multicomponent systems [18,19]. This new model takes the formation energies of the Cs and Ps into account and allows formulating equations for calculation of their equilibrium concentrations.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Modelling of short-range ordering kinetics in dilute multicomponent substitutional solid solutions

Svoboda

Holec

Popov

et al. 2020

Philosophical Magazine

Self Cite

View full text Add to dashboard Cite

Short-range ordering as the formation of couples and pairs between solutes is affected by their formation energies. This is not reflected in the standard regular solution model. Here, we present a new thermodynamic model which accounts for the dependence of the molar Gibbs energy on the concentrations of couples and pairs and their formation energies. The model treats kinetics of couples and pairs formation controlled by diffusion. This new model uses tracer diffusion coefficients of solutes and bond formation energies, which can be taken from ab initio calculations. Insofar, the current concept bridges the gap between ab initio methods and non-equilibrium thermodynamics. The reliability of the model is checked by comparison with kinetic Monte Carlo simulations. The model is applied to an Al-Mg-Si-Cu system. Finally, the configurational entropy for a binary system evaluated with the current model is compared with Bethe's approximation, which allows estimating of applicability limits of the current model.

show abstract

“…With this formulation, we have improved the configurational entropy of a system with couples and pairs, compared to previous formulations in the literature, see also [18,19].…”

Section: Determination Of Configurational Entropymentioning

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Modelling of short-range ordering kinetics in dilute multicomponent substitutional solid solutions

Svoboda

Holec

Popov

et al. 2020

Philosophical Magazine

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to the assumption that the system is dilute in B and C, other lattice positions than those mentioned above participate in a negligible amount in the system. The justification for introducing subsystems is outlined in more detail in [25]. Finally, the factor 1 2, assigned to c BB and c CC in the last term of equation (12), corresponds to the fact that each pair has two atoms of the same component.…”

Section: Gibbs Energy Of the Systemmentioning

confidence: 99%

“…(i) In the first part the arrangement of lattice positions into three subsystems, related to the existence of a solute atom as nearest neighbour atom, is performed. The configurational entropy of each subsystem is described by the prominent Bragg-Williams approximation, for details see [25,26]. (ii) In the second part the kinetics of couples and pairs formation is investigated.…”

Section: Introductionmentioning

confidence: 99%

Couples and pairs formation—thermodynamic and kinetic modelling applied to Al–Mg–Si

Svoboda

Shan

Kozeschnik

et al. 2017

Modelling Simul. Mater. Sci. Eng.

View full text Add to dashboard Cite

Kinetics of formation of couples (B–C) and pairs (B–B, C–C) is studied in an alloy with B-atoms and C-atoms as dilute solutes and A-atoms as solvent. The trapping concept, allowing division of the system into subsystems, the Bragg–Williams approximation used for the configurational entropy of each subsystem, and the thermodynamic extremal principle are applied in the model. The derived equilibrium conditions provide an extended Oriani-type equation. The kinetics of couples and pairs formation is given by explicit ordinary differential equations for the concentrations of couples and pairs allowing calculation of all relevant state variables. The concept is applied to an Al–Mg–Si system with the bonding energy terms E BB, E CC, E BC taken from ab-initio calculations. The presence of excess vacancies that are eventually frozen in by instant quenching as well as their subsequent annihilation influence the formation kinetics in a decisive way.

show abstract

“…Most recently the authors of this paper introduced a more accurate treatment of the interaction energy between solvent A and solute B in a binary system. The according model has been denominated as the self-consistent model, see [4], since it accounts for the number of A-A, A-B and B-B bonds in equilibrium in dependence on the interatomic interaction energies. Now the authors succeeded in generalizing this self-consistent model for multi-component systems.…”

mentioning

confidence: 99%