Phase Stability in Mechanically Alloyed Mg–Ni System Studied by Experiments and Thermodynamic Calculations

In this study, tungsten silicide powders mechanochemically synthesized using WO3-SiO2-Mg powder blends. Stoichiometric proportions and excess amounts of initial powders were used to indicate the effects of final composition of synthesized tungsten silicide powders. Since the initial powder compositions affect the reaction times, all compositions were mechanically alloyed for 1 hour. In addition, thermodynamic calculations of all compositions were theoretically conducted. The dominant phases are WSi2 and MgO for all mechanically alloyed powders. Results show that the excess amount additions of initial powders directly effects the amount and formation of resultant phases in the synthesized powder compositions.

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On the Effectiveness of Nature-Inspired Metaheuristic Algorithms for Performing Phase Equilibrium Thermodynamic Calculations

The Scientific World JOURNAL ◽

10.1155/2014/374510 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 7

Author(s):

Seif-Eddeen K. Fateen ◽

Adrian Bonilla-Petriciolet

Keyword(s):

Phase Equilibrium ◽

Phase Stability ◽

Equilibrium Problems ◽

Cuckoo Search ◽

Optimization Method ◽

Metaheuristic Algorithms ◽

Thermodynamic Calculations ◽

Efficient Global Optimization ◽

Krill Herd Algorithm ◽

Krill Herd

The search for reliable and efficient global optimization algorithms for solving phase stability and phase equilibrium problems in applied thermodynamics is an ongoing area of research. In this study, we evaluated and compared the reliability and efficiency of eight selected nature-inspired metaheuristic algorithms for solving difficult phase stability and phase equilibrium problems. These algorithms are the cuckoo search (CS), intelligent firefly (IFA), bat (BA), artificial bee colony (ABC), MAKHA, a hybrid between monkey algorithm and krill herd algorithm, covariance matrix adaptation evolution strategy (CMAES), magnetic charged system search (MCSS), and bare bones particle swarm optimization (BBPSO). The results clearly showed that CS is the most reliable of all methods as it successfully solved all thermodynamic problems tested in this study. CS proved to be a promising nature-inspired optimization method to perform applied thermodynamic calculations for process design.

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Phase Stability in the Al(6−x)CuxZr2 System for 0 < × < 1.

MRS Proceedings ◽

10.1557/proc-186-439 ◽

1990 ◽

Vol 186 ◽

Cited By ~ 4

Author(s):

P. B. Desch ◽

R. B. Schwarz ◽

P. Nash

Keyword(s):

Thermal Stability ◽

Phase Stability ◽

Single Phase ◽

Lattice Parameter ◽

Elemental Powder ◽

Mechanically Alloyed ◽

Two Phase ◽

Powder Mixtures ◽

Phase Mixture ◽

Thermal Stability Of

AbstractWe have determined the structures and thermal stability of AI(6-x) CuxZr2 (0≤ × ≤ 1) powders prepared by mechanically alloying elemental powder mixtures. In the as mechanically alloyed condition the structure is L12 for all ×. After heating to 750°C the alloy is single phase D023 for 0 < × < 0.2, is a two-phase mixture of D023 and L12 for 0.2 < × < 0.6, and remains in the Ll2 phase for 0.6 < × < 1. Al5CuZr2 is stable in the Ll2 structure up to 1300°C. The lattice parameter of the annealed L12 phase is Independent of ×.

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The Phase Stability in the Fe-B Binary System: Comparison between the Interstitial and Substitutional Models

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.322.1 ◽

2012 ◽

Vol 322 ◽

pp. 1-9 ◽

Cited By ~ 8

Author(s):

Z. Nait Abdellah ◽

Redoune Chegroune ◽

Mourad Keddam ◽

B. Bouarour ◽

L. Haddour ◽

...

Keyword(s):

Binary System ◽

Phase Diagrams ◽

Solid Solutions ◽

Phase Stability ◽

Thermodynamic Stability ◽

Thermodynamic Study ◽

Thermodynamic Calculations ◽

Chemical Potentials ◽

Two Phases ◽

Good Agreement

In the present work, a thermodynamic study was carried out in order to analyze the thermodynamic stability of the and phases in equilibrium with the phase using the calculation of phase diagrams (Calphad) formalism. The two phases and are modelled as substitutional and interstitial solid solutions of boron. The expressions of the chemical potentials ofBandFeare derived in both phases to perform the thermodynamic calculations. A comparison is made between the results provided by the substitutional and interstitial models and good agreement is observed between these two models.

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