Subsolidus phase relations in Ca2Mo2O8–NaEuMo2O8-powellite solid solution predicted from static lattice energy calculations and Monte Carlo simulations

2008 ◽  
Vol 10 (24) ◽  
pp. 3509 ◽  
Author(s):  
Victor L. Vinograd ◽  
Dirk Bosbach ◽  
Björn Winkler ◽  
Julian D. Gale
Keyword(s):  
Solid Solution ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Lattice Energy ◽  
Phase Relations ◽  
Subsolidus Phase ◽  
Energy Calculations ◽  
Static Lattice

Examination of Solid-Solution Phase Formation Rules for High Entropy Alloys from Atomistic Monte Carlo Simulations

JOM ◽  
2015 ◽  
Vol 67 (10) ◽  
pp. 2364-2374 ◽  
Author(s):  
Zhenyu Liu ◽  
Yinkai Lei ◽  
Corinne Gray ◽  
Guofeng Wang
Keyword(s):  
Solid Solution ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Phase Formation ◽  
Solution Phase ◽  
Solid Solution Phase ◽  
High Entropy Alloys ◽  
High Entropy

scholarly journals Structural Transition of Vacancy-Solute Complexes in Al-Mg-Si Alloys

Metals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 2
Author(s):  
Masataka Mizuno ◽  
Kazuki Sugita ◽  
Hideki Araki
Keyword(s):  
Solid Solution ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
First Principles ◽  
Structural Transition ◽  
First Principles Calculations ◽  
Eye Formation

To theoretically examine the structural transition of vacancy–solute complexes in Al–Mg–Si alloys, we performed first-principles calculations for layered vacancy–solute complexes with additional Mg atoms. The central Mg atom in the additional Mg layer shifted to the Si layer with the increase in the number of Mg atoms to weaken the repulsive Mg–Mg interaction and to form Mg–Si bonds. When five Mg atoms were added to the layered vacancy–solute complex, the central Mg atom completely shifted to the Si layer, and a Mg vacancy was formed in the Mg layer, which indicated that the β″-eye is formed upon the addition of Mg atoms. We reproduced β″-eye formation from a solid solution with a vacancy using first-principles-based Monte Carlo simulations. Once the β″-eye was formed on the layered vacancy–solute complex, the process can be repeated by the formation of alternate Mg and Si layers along [010] β″. These results clearly indicate that the layered vacancy–solute complex plays an important role in β″-eye formation.

scholarly journals Configurational Entropy in Multicomponent Alloys: Matrix Formulation from Ab Initio Based Hamiltonian and Application to the FCC Cr-Fe-Mn-Ni System

Entropy ◽  
2019 ◽  
Vol 21 (1) ◽  
pp. 68 ◽  
Author(s):  
Antonio Fernández-Caballero ◽  
Mark Fedorov ◽  
Jan Wróbel ◽  
Paul Mummery ◽  
Duc Nguyen-Manh
Keyword(s):  
Solid Solution ◽  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Ab Initio ◽  
Density Functional ◽  
Elevated Temperatures ◽  
Thermodynamic Integration ◽  
Matrix Formulation ◽  
Configuration Entropy ◽  
Multi Body

Configuration entropy is believed to stabilize disordered solid solution phases in multicomponent systems at elevated temperatures over intermetallic compounds by lowering the Gibbs free energy. Traditionally, the increment of configuration entropy with temperature was computed by time-consuming thermodynamic integration methods. In this work, a new formalism based on a hybrid combination of the Cluster Expansion (CE) Hamiltonian and Monte Carlo simulations is developed to predict the configuration entropy as a function of temperature from multi-body cluster probability in a multi-component system with arbitrary average composition. The multi-body probabilities are worked out by explicit inversion and direct product of a matrix formulation within orthonomal sets of point functions in the clusters obtained from symmetry independent correlation functions. The matrix quantities are determined from semi canonical Monte Carlo simulations with Effective Cluster Interactions (ECIs) derived from Density Functional Theory (DFT) calculations. The formalism is applied to analyze the 4-body cluster probabilities for the quaternary system Cr-Fe-Mn-Ni as a function of temperature and alloy concentration. It is shown that, for two specific compositions (Cr 25Fe 25Mn 25Ni 25 and Cr 18Fe 27Mn 27Ni 28), the high value of probabilities for Cr-Fe-Fe-Fe and Mn-Mn-Ni-Ni are strongly correlated with the presence of the ordered phases L1 2 -CrFe 3 and L1 0-MnNi, respectively. These results are in an excellent agreement with predictions of these ground state structures by ab initio calculations. The general formalism is used to investigate the configuration entropy as a function of temperature and for 285 different alloy compositions. It is found that our matrix formulation of cluster probabilities provides an efficient tool to compute configuration entropy in multi-component alloys in a comparison with the result obtained by the thermodynamic integration method. At high temperatures, it is shown that many-body cluster correlations still play an important role in understanding the configuration entropy before reaching the solid solution limit of high-entroy alloys (HEAs).

Subsolidus phase relations of the Dy-Fe-Al system

2011 ◽  
Vol 26 (1) ◽  
pp. 9-15
Author(s):  
Y. Q. Chen ◽  
J. K. Liang ◽  
J. Luo ◽  
J. B. Li ◽  
G. H. Rao
Keyword(s):  
Solid Solution ◽  
Phase Relations ◽  
Unit Cell Parameters ◽  
Subsolidus Phase ◽  
X Ray ◽  
Cell Parameters ◽  
Ternary Compounds ◽  
Al Content ◽  
Three Phase ◽  
Binary Compounds

The subsolidus phase relations of the Dy-Fe-Al system have been investigated by means of X-ray powder diffraction. There are 5 ternary compounds, 10 binary compounds, and 21 three-phase regions in this system. The solid-solution regions of Dy(Fe1−xAlx)2, DyFe3−xAlx, Dy2(Fe1−xAlx)17, and DyFe12−xAlx have been determined based on the dependence of their unit-cell parameters on the Al content.

Subsolidus phase relations in La2O3–Bi2O3–CuO

1999 ◽  
Vol 14 (4) ◽  
pp. 274-275 ◽  
Author(s):  
X. L. Chen ◽  
W. Eysel
Keyword(s):  
Solid Solution ◽  
Ternary System ◽  
Powder Diffraction ◽  
Binary Compound ◽  
Phase Relations ◽  
Ternary Solid Solution ◽  
Solid Solution Series ◽  
Subsolidus Phase ◽  
X Ray ◽  
Solution Series

The subsolidus phase relations in the ternary system La2O3–Bi2O3–CuO at 900 °C were investigated by X-ray powder diffraction. A new binary compound, Bi2La4O9, was found, as well as a binary and a ternary solid solution series, Bi1−xLaxO1.5 (0.16≤x≤0.33) and La2−xBixCuO4 (0≤x≤0.11), respectively.

Sign in / Sign up

Export Citation Format

Share Document