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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]

This paper reports the thermodynamic analysis of (Co-Cr) system using THERMO-calc package (basis for CALPHAD) and PBIN database. Calculations involve binary phase diagram, Gibb's energy curve and activity curve at three different elevated temperatures 2125K, 2150K and 2175K. Induced miscibility gap is observed at particular concentration. Binary phase diagram shows variation in phases in prescribed alloy with increasing temperature and mole fraction concentration of . The total Gibbs energy decreases with increasing temperature showing the stability of Co-Cr system. Activity showed thorough fluctuation resulting in negative deviation from Raoult's law ideal curve. [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]

[Display omitted] • A computational materials design to develop novel single crystal superalloys. • Achieving design balance of multi-objective properties. • Comprehensive design through DFT, empirical models, CALPHAD, and machine learning. • 12 alloys selected from 779,625 alloys in trade-offs between different factors. The computational materials design is performed to develop novel single crystal superalloys with balance of multi-objective properties. The entire design process is carried out by materials computation from systems selection to composition determination. The design rules are proposed to optimize compositions of Ni-based single crystal superalloys for materials characteristics, using first-principles calculations, CALPHAD calculations, theoretical models, and machine learning. By first-principles calculations, the effect of alloying elements on structural, elastic, electronic properties of Ni 3 Al are investigated and the Ni-Al-V-Cr-Nb-Mo-Ta-W-Re systems are determ5ined. Application of theoretical models and CALPHAD calculations allows the large materials exploring space to become narrow, based on materials design criterion: microstructure, density, castability, and processability. The creep resistance of remained alloys is estimated by using machine learning and creep merit index. There are 12 alloys selected from 779,625 composition combinations, reaching the balance of multiple design properties. With comparing to commercial superalloys, the selected alloy has excellent performance in trade-offs between different factors, specifically prominent in the aspect of Cr-Al space of oxidation resistance. This design procedure is expected to reduce excessive consumption of cost and time in the process of trial-and-error testing, providing a guide on developing potential Ni-based superalloys systems. [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]