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The C-Mo-Zr system was assessed by means of the CALPHAD approach. All of the phase equilibria available from the literature were critically reviewed. The liquid was modeled as substitutional solution phase, while the carbides including fcc-(Mo,Zr)C1−x, bcc-(Mo), bcc-(Zr), hcp-Mo2C, hcp-(Zr) and η-MoC were described by using corresponding sublattice models. The laves-Mo2Zr and shp-MoC phases were considered as binary compounds with no solubility for the third component. The existence of ternary phase was not reported in this system. The modeling of C-Mo-Zr ternary system covers the entire composition and temperature ranges, and a set of self-consistent thermodynamic parameters for the C-Mo-Zr system was systematically optimized. Comprehensive comparisons between the calculated and reported phase diagram data show that the reliable information is satisfactorily accounted for by the present modeling. The liquidus projection and reaction scheme of the C-Mo-Zr system were also generated based on the present thermodynamic assessment. [ABSTRACT FROM AUTHOR]

The Mo–W–N and C–Mo–W ternary systems have been critically evaluated by means of the CALPHAD approach, wherein the C–Mo–W system was reassessed to ensure the model consistency. The Gibbs energies of individual phases in the ternary systems are described with corresponding models, such as substitutional solution model and sublattice model. A set of self-consistent thermodynamic parameters is obtained. Comprehensive comparisons between the calculated and reported phase diagram data show that the reliable information is satisfactorily accounted for by the present modeling. Based on the present work together with the previously reported assessments of C–Mo–N and C–W–N ternary sub-systems, a thermodynamic description of the C–Mo–W–N quaternary system is obtained and used to calculate the phase equilibria and thermodynamic stability of the hexagonal structured (Mo,W)(C,N) carbonitride phase. [ABSTRACT FROM AUTHOR]

The Ta–Mo–C system was assessed by means of the CALPHAD approach. All of the phase diagram and thermodynamic information available from the literature were critically reviewed. The liquid was modeled as substitutional solution phase, while the carbides including fcc-(Mo,Ta)C 1- x , bcc-(Mo,Ta), hcp-(Mo,Ta) 2 C and η-MoC were described by using corresponding sublattice models. The ζ-Ta 4 C 3- x was considered as a linear compound with carbon content fixed, while shp-MoC was treated to be a binary stoichiometric phase. There was no ternary compound reported in this system. The modeling of Ta–Mo–C ternary system covers the entire composition and temperature ranges, and a set of self-consistent thermodynamic parameters for the Ta–Mo–C system was systematically optimized. Comprehensive comparisons between the calculated and reported phase diagram and thermodynamic data show that the reliable information is satisfactorily accounted for by the present modeling. The liquidus projection and reaction scheme of the Ta–Mo–C system were also generated by using the present thermodynamic parameters. [ABSTRACT FROM AUTHOR]

The C-Co-Mo-W and C-Mo-Ni-W quaternary systems have been critically evaluated by means of the CALPHAD approach, in which the Co-Mo-W system was readjusted to ensure the model consistency. The thermodynamic models of Gibbs energies for individual phases in the ternary and quaternary systems are described, including substitutional solution model, sublattice model and linear compound model. The modeling covers the whole temperature and composition ranges, and a set of self-consistent thermodynamic parameters for the C-Co-Mo-W and C-Mo-Ni-W quaternary systems is obtained. According to the comprehensive comparisons between the reported and calculated phase diagram data, the reliable equilibria information is satisfactorily accounted for by the modeling. Based on the present work together with the previously reported assessments of binary, ternary and quaternary sub-systems, a thermodynamic database for the C-Co-Mo-Ni-W quinary system is constructed and applied to calculate the sintering region phase equilibria of the (W,Mo)C-(Co,Ni) cemented carbides. • Thermodynamic evaluations of C-Mo-W-Co/Ni quaternary systems are performed. • Reliable experimental data are well accounted for by the present modeling. • Calculated sintering region of (W,Mo)C-(Co,Ni) cemented carbides are presented. • The assessment is important to the design of (W,Mo)C-based cemented carbides. [ABSTRACT FROM AUTHOR]

• The massive phase equilibria information of 6016 alloys is calculated based on HTC. • A Python-based program AEET is developed to realize high-throughput calculations. • Reasonable criteria are applied to filter the appropriate 6016 alloy compositions. • This method is promising for the composition selection of industrial materials. In the present work, high-throughput calculation (HTC) method is performed to obtain the phase equilibria of solidified 6016 Al-alloys. The calculations of primary phase fraction, precipitates fraction and phase composition are realized based on the Scheil-Gulliver solidification model of Thermo-Calc software, and the entire composition ranges of standard 6016 Al-alloy is taken into account. A Python-based program called Automatic Execution and Extraction Tasks (AEET) is developed, it automatically generate the commands of calculations, execute the Thermo-Calc software and then extract the key data of output files. The obtained results are listed in an Excel file, which is convenient for the subsequent visualization analysis and machine learning. Several criteria are combined to filter the appropriate compositions of industrial 6016 Al-alloys, providing a valuable guidance to the experimentalists and avoiding unnecessary trial-and-error tests. This HTC approach is not limited to the solidification modelings; it can be extended to any kinds of thermodynamic and kinetic calculations. [ABSTRACT FROM AUTHOR]

Among the ternary borides, the Mo–Co–B system is of great interest because of its excellent hardness, toughness, and stability performance. Eight samples with 60 at.% Co were designed to investigate the isothermal section of Mo–Co–B system at 1073 K in the Co-rich portion. Scanning electron microscopy, energy-dispersion spectroscopy, electron probe microanalysis, differential scanning calorimetry, and X-ray diffraction were used to investigate the phase equilibria of the samples. The formation enthalpies of the ternary borides were obtained by first-principles calculations to serve as key information for thermodynamic assessment. By coupling the reviewed experimental data from the literature, the presently determined phase equilibria, and the calculated formation enthalpies of the compounds, the thermodynamic parameters for the Mo–Co–B ternary system were optimized and used to calculate the isothermal sections, vertical section, and liquidus projection of the system. Comprehensive comparisons showed that the calculated results are in reasonable agreement with the reported phase diagram and thermodynamic data. [ABSTRACT FROM AUTHOR]

The phase field model for multicomponent alloys are usually coupled with the thermodynamic database. But it will take much time to solve the quasi phase equilibrium equations. In order to reduce such time and keep the enough accuracy, we develop a new model to predict the quasi phase equilibrium based on the machine learning method. As an example, the quasi phase equilibrium during the isothermal solidification of Al-Cu-Mg alloy is studied in detail. A neural network model with 3 inputs, 4 outputs and a hidden layer of 150 nodes is constructed. The "training data" are prepared by solving the quasi phase equilibrium equations with least square method. The neural network model is trained by different amount of data set, which can fully cover the ranges of all the variables. The accuracy and performance of the neural network model are discussed in detail. Its high accuracy and fast speed demonstrated that this will be a convenient method to acquire the quasi phase equilibrium data in phase field model for multicomponent alloys. [ABSTRACT FROM AUTHOR]