CALPHAD Method Research Articles

Multiscale modeling-driven synthesis of Cu40Zn24Ni24Ag8Hg4 high entropy alloy with antibacterial properties

High-entropy alloys (HEAs) are promising materials across various sectors, yet their potential as antibacterial powders remain underexplored. In this study, we synthesized a novel Cu-Zn-Ni-Ag-Hg-based HEA using CALPHAD and DFT methods coupled with mechanical alloying. The HEA's antibacterial efficacy against Staphylococcus aureus (S. aureus) and Escherichia coli (E. Coli) was systematically evaluated. Computational and experimental analyses confirmed the HEA's single-phase FCC structure. Mechanical alloying for 8 h facilitated the formation of the single-phase HEA, with Ni and Cu initially dissolving into each other, followed by Zn, Ag, and Hg. Antibacterial testing demonstrated minimum inhibitory concentrations of 400 µg/mL for S. aureus and 600 µg/mL for E. coli, highlighting the broad-spectrum antibacterial properties of the synthesized HEA. These results underscore the potential of HEAs in advancing antibacterial materials for biomedical applications.

Effect of Nb on hydrogen storage properties of Ti–V–Cr-based alloys

This research investigates the impact of incorporating Nb into Ti–V–Cr-based alloys, with compositions ranging from Ti30-xV35Cr35Nbx (x = 0, 5, 10, 15, and 20 at. %), with the objective of enhancing hydrogen storage properties. Employing a comprehensive approach encompassing design, synthesis, and characterization, the study aimed to develop novel hydrogen storage alloys. Utilizing the CALPHAD method, the alloys were designed to anticipate the formation of multicomponent single-phase structures. Structural and microstructural analyses of the synthesized alloys were conducted using XRD, SEM, and EDS techniques. The hydrogen storage capabilities were evaluated utilizing a Sieverts’ type apparatus. The investigated alloys displayed a singular-phase BCC solid solution, characterized by dendritic microstructures. Notably, the Nb-free alloy, Ti30V35Cr35, demonstrated the highest hydrogen storage capacity, reaching 3.62 wt% (∼1.9 H/M) under 20 bar of H2 at room temperature. Among the Nb-containing alloys, Ti25V35Cr35Nb5 exhibited a capacity of 2.91 wt% (∼1.6 H/M) under identical conditions. Furthermore, the incorporation of Nb up to 10 at. % effectively bolstered cycle durability. This study underscores the presence of an optimal Nb content crucial for achieving the highest hydrogen capacity and cycle durability in these alloys.

Development of the interlayer alloy using for TLP diffusion bonding of GH3230 superalloy based on the CALPHAD method

The hot-end components of aero-engines and gas turbines not only require high-temperature alloys capable of withstanding extreme temperatures, but also demand welds with high-temperature-resistant properties. In this study, the CALPHAD method was employed, utilizing the thermodynamic theory of phase diagrams with Thermo-Calc software and the corresponding database, to design the interlayer composition for superalloy TLP diffusion connections. The optimization aimed to determine the interlayer material's solidus-liquidus and compound phase content, resulting in the selection of a new nickel-based interlayer material containing B as MPD, with Co and W as strengthening elements. Using GH3230 alloy as the research subject, TLP diffusion bonding experiments were conducted at a welding temperature of 1200 °C with a holding time of 4 h. The weld zone exhibited no defects, and the microstructure was identical to that of the GH3230 base metal, consisting entirely of a solid solution. High-temperature tensile tests revealed that fractures consistently occurred in the GH3230 base metal, indicating that the weld's strength significantly exceeded that of the base metal. The average tensile strength of GH3230 high-temperature alloy bar tensile simulated specimens is 899 MPa at room temperature and 213 MPa at high temperature. In addition, the 90° three-point bend test showed no cracking in the weld area, indicating adequate plasticity.

A single-phase Nb25Ti35V5Zr35 refractory high-entropy alloy with excellent strength-ductility synergy

Refractory high entropy alloys (RHEAs) are promising candidates for high-temperature structural materials due to their excellent high-temperature performance. However, the room-temperature brittleness of most alloys results in poor plastic formability, thereby limiting their engineering applications. In this study, Nb25Ti35V5Zr35 alloy with cold-rollability was developed, and its phase stability, tensile mechanical properties, elastic properties, strengthening mechanism, and deformation mechanism were investigated by combining experiments, CALPHAD, DFT and molecular statics (MS) methods. The results demonstrate that Nb25Ti35V5Zr35 alloy possesses good phase stability, with both the as-cast and annealed states maintaining a single-phase BCC structure without undergoing phase transformation. The tensile yield strength of the alloy reaches its peak at 1152 MPa in the cold-rolled condition, while its annealed state exhibits an optimal balance of strength and plasticity, with a yield strength of 836 MPa and an elongation of 22.45 %, respectively. Solid solution strengthening is the primary source of its high strength, with V and Zr playing key roles in this strengthening mechanism. Dislocation slip plays a dominant role in plastic deformation. Additionally, compared to traditional BCC alloys, the significance of edge dislocations in the deformation process is notably enhanced, with the {112} plane serving as the preferred slip plane for dislocations. DFT results indicate that the alloy exhibits significant anisotropy in both Young's modulus and shear modulus. This work contributes to understanding the material properties of the Nb25Ti35V5Zr35 alloy and provides a reference for the design of new ductile RHEAs.

Thermodynamic investigation of reduced barium molybdates

Precise identification and thermodynamic assessment of the various phases in spent nuclear fuel are necessary for the accurate dynamic modeling of nuclear fuel. The Thermodynamics of Advanced Fuels – International Database (TAF-ID) compiles high-quality, self-consistent, and reliable thermodynamic data of various phases in chemical systems of interest for the international nuclear industry, such as the Ba-Mo-O ternary system. The thermodynamic properties of compounds in the Ba-Mo-O ternary system, especially those of hexavalent Mo, have been extensively studied and included in computational thermodynamic assessments. In contrast, compounds with Mo in reduced oxidation states, such as BaMo6O10 and Ba3Mo18O28, have been excluded from such assessments due to a lack of experimentally assessed thermodynamic data. In this work, high-quality samples of the aforementioned compounds were synthesized, and the first experimental assessment of their heat capacities in the temperature range 300–600 K were obtained. Furthermore, a reversible phase transition was identified at ∼380 K for BaMo6O10. The collected experimentally-assessed thermodynamic data from this work and initial calculated estimations of standard enthalpies of formation and entropies for these compounds were successfully integrated into a preliminary, updated Ba-Mo-O thermodynamic assessment using the CALPHAD method. Key thermodynamic properties of the newly included compounds (i.e., standard enthalpy of formation and entropy) were calculated using the new Ba-Mo-O assessment.

Influence of substitution of Cr by Cu on phase equilibria and microstructures in the Fe–Ni–Co–Cr high-entropy alloys

The article describes how substitution of chromium by copper affects phase equilibria in Fe–Ni–Co–Cr high-entropy alloy. The alloys with copper content ranging from 0 to 20 % (at.) of Cu were prepared. The alloys were equilibrated at 900, 800, 700, and 650 °C. The samples were investigated by electron microscopy, EDX spectroscopy, and EBSD method. The face-centred cubic phases have only occurred in equilibrated alloys: austenite matrix, copper-rich FCC(Cu) phase, and regions containing these phases. The compositions of equilibrated samples at annealing temperatures are given. Fine microstructures including a semicoherent FCC phase rich in Cu and an FCC phase including the main magnetic elements (Fe, Co, Ni) were formed. The experimental results were compared with the calculated phase equilibria obtained by the CALPHAD method.

Effects of Different Zinc Content on Solidification, Microstructure, and Mechanical Properties in Tin–Bismuth Alloy

The present aims to evaluate the effect of adding Zn (0.5% and 9.0% in wt%) on phase transformation temperatures, microstructure coarsening, solidification parameters (cooling rate‐L and growth rate‐VL), macrosegregation, and mechanical properties of directionally solidified Sn‐34wt%Bi‐xZn alloys. The samples have been characterized by optical microscopy, scanning electron microscopy, X‐ray fluorescence, and X‐ray diffraction, in addition to Vickers microhardness and tensile tests. The CALPHAD method has been used for thermodynamic computations via Thermo‐calc software, in order to obtain thermodynamic data. The microstructure of Sn–Bi–Zn alloys is mainly dendritic, composed of a Sn‐rich matrix (β‐Sn) with Bi precipitates inside and surrounded by a Sn+Bi eutectic mixture of phases, predominantly observed at the coarse scale. Coarse Zn needles are also observed in the Sn‐34wt%Bi‐9wt%Zn alloy due to the high Zn content. On the whole, Zn provoked a coarsening of the dendritic arrangement. Moreover, Zn additions cause inverse segregation of Bi, as compared to the rather constant macrosegregation profile observed in the binary Sn–Bi alloy. On the whole, both additions of Zn (0.5 and 9.0) promoted increase in Vickers microhardness, yield strength (σY), and ultimate tensile strength (σu), however, causing an overall reduction in elongation‐to‐fracture (δ).

High-throughput strategy to design high entropy alloys with an FCC matrix, L12 precipitates, and optimized yield stress

This work proposes a methodology for designing high-strength precipitation-hardened high entropy alloys (HEAs) with an FCC matrix and L12 precipitates. High-throughput solidification calculations were conducted using the CALPHAD method, evaluating 11,235 alloys in the Cr-Co-Ni-Al-Ti system under specific boundary conditions. The acquired information was used to filter the alloys, focusing on alloys exhibiting an FCC+L12 phase field at 750 °C, a solidification interval narrower than 100 °C, and a solvus temperature under 1100 °C. The filtered alloys were analyzed to estimate their solid solution and precipitation hardening contributions to yield strength, with antiphase boundary energy (APB) assessed using two models. Three alloys were selected for testing the proposed strategy, including one with the highest yield stress and others for comparison. These alloys were produced, processed, and characterized using DSC, synchrotron XRD, SEM, and TEM. The results showed that the desired microstructure was achieved, with the alloys consisting of an FCC matrix and a high-volume fraction of L12 precipitates. Tensile tests at room temperature, 650 °C, 750 °C, and 850 °C demonstrated that the proposed model predicts well the yield strength trends, demonstrating the potential of the proposed approach for accelerating the discovery and development of novel HEAs with tailored properties.

Experimental Validation of Property Models and Databases for Computational Superalloy Design

Computational superalloy development is a powerful alternative to the conventional experimental approach. Based on thermodynamic databases and the CALPHAD method, it is possible to estimate the properties of a large number of potential alloys and select the most promising ones. However, the accuracy of the databases and complementary property models can be unsatisfying. The accuracy of two mass density and lattice parameter models and the TTNI8 and TCNI10 databases is analyzed in detail on the experimental basis of computationally optimized single‐crystalline superalloys. Various properties are measured and compared to the results of the property models and databases. Neither of the databases is superior to the other and especially the solvus temperature is not accurately described in both. The new mass density model, a linear regression based on the molar mass, is more reliable for low‐density alloys. Both lattice parameter model versions slightly overestimate the room‐temperature lattice parameter. The lattice parameter, however, is more accurately calculated using the new model version. The results of this study can be readily used to improve a multicriteria alloy optimization tool for computational superalloy design.

Computational thermodynamics-guided alloy design and phase stability in CoCrFeMnNi-based medium-and high-entropy alloys: An experimental-theoretical study

A computational thermodynamics approach has been employed to design CoCrFeMnNi-based medium- and high-entropy alloys (M/HEAs) with systematically varied compositions (Co((80-X)/2)Cr((80-X)/2)FeXMn10Ni10 with x = 30, 40, and 50 at.%) and phase stability. Since the formation of sigma phase, usually brittle and undesirable, is a common concern, when this class of alloys is subjected to elevated temperatures (600–1000 °C), predicting its formation becomes essential. Thus, its formation and the phase equilibria were studied using the CALPHAD method, and two empirical methods, namely, valence electron concentration (VEC) and paired sigma-forming element (PSFE). Isothermal aging treatments at 900–1100 °C for 20 h were performed, since CALPHAD and VEC/PSFE predictions diverged. Both prediction methods were compared with experimental characterization by a combination of scanning electron microscopy and high-energy synchrotron X-ray diffraction. The predictions from the VEC/PSFE and CALPHAD calculations (depending on the database used) were shown to be quite accurate.

Thermodynamic behavior of CrF2 corrosion product in the molten LiF-ThF4 salt system

This work examines the thermochemistry of the chromium difluoride CrF2 corrosion product in the molten ▪ fuel salt system. Through a combination of experimental investigations and thermodynamic modeling assessment, the study elucidates the thermodynamic properties, phase diagram equilibria, and overall thermodynamic behavior of CrF2 corrosion product, following dissolution from a structural material to the molten salt fuel environment. In this work, two different synthesis methods were developed for pure CrF2, further allowing to experimentally measure the phase equilibria in the ▪ , ▪ , and ▪ systems. Then, thermodynamic models were developed using the CALPHAD method based on the quasichemical model in the quadruplet approximation.

Phase Transformations after Heat Treating an As-Cast Fe-30Mn-8.8Al-0.3Si-0.15C Steel

The phase transformations in an as-cast Fe-30Mn-8.8Al-0.3Si-0.15C steel were analyzed experimentally and numerically with a Calphad-based method during heat treatment. The nonequilibrium phases were determined using the Thermo-Calc Scheil module and the equilibrium phases with Themo-Calc based on the steel chemical composition. The precipitated phases were analyzed with TC-PRISMA using the chemical composition, nucleation site, and temperature among other factors. An ingot of this chemical composition was vacuum-melted using pure elements under an Ar gas atmosphere. As-cast steel specimens were annealed and solution-treated, quenched, and then aged at different temperatures. Heat-treated specimens were analyzed by different techniques. The results indicated that the microconstituents are the α and γ phases for the as-cast, homogenized, and quenched conditions. The main difference among these conditions is the distribution and size of the γ phase, which produced a change in hardness from 209 to 259 VHN. In contrast, the aging treatment at 750 °C caused a decrease in hardness from 492 to 306 VHN, which is attributable to the increase in volume fraction of the γ phase. On the other hand, the aging treatment at 550 °C promoted precipitation hardening from 259 to 649 VHN because of the κ precipitate formation. The calculated results for the different heat treatments with the Calphad-based method agreed well with the experimental ones. In addition, the intragranular precipitation of the κ phase could be simulated using the nucleation and growth and coarsening mechanisms based on a Calphad method.

Atomistic Origins of Various Luminescent Centers and n-Type Conductivity in GaN: Exploring the Point Defects Induced by Cr, Mn, and O through an Ab Initio Thermodynamic Approach.

GaN is a technologically indispensable material for various optoelectronic properties, mainly due to the dopant-induced or native atomic-scale point defects that can create single photon emitters, a range of luminescence bands, and n- or p-type conductivities. Among the various dopants, chromium and manganese-induced defects have been of particular interest over the past few years, because some of them contribute to our present-day light-emitting diode (LED) and spintronic technologies. However, the nature of such atomistic centers in Cr and Mn-doped GaN is yet to be understood. A comprehensive defect thermodynamic analysis of Cr- and Mn-induced defects is essential for their engineering in GaN crystals because by mapping out the defect stabilities as a function of crystal growth parameters, we can maximize the concentration of the target point defects. We therefore investigate chromium and manganese-induced defects in GaN with ab initio methods using the highly accurate exchange-correlation hybrid functionals, and the phase transformations upon excess incorporation of these dopants using the CALPHAD method. We also investigate the impact of oxygen codoping that can be unintentionally incorporated during crystal growth. Our analysis sheds light on the atomistic cause of the unintentional n-type conductivity in GaN, being ON-related. In the case of Cr doping, the formation of CrGa defects is the most dominant, with an E +/0 charge transition at E VBM + 2.19 eV. Increasing nitrogen partial pressure tends to enhance the concentration of CrGa. However, in the case of doping with Mn, several different Mn-related centers can form depending on the growth conditions, with MnGa being the most dominant. MnGa possesses the E 2+/+, E +/0, and E 0/- charge transitions at 0.56, 1.04, and 2.10 eV above the VBM. The incorporation of oxygen tends to cause the formation of the MnGa-VGa center, which explains a series of prior experimental observations in Mn-doped GaN. We provide a powerful tool for point defect engineering in wide band gap binary semiconductors that can be readily used to design optimal crystal growth protocols.

Effect of laser energy density on cracking susceptibility and wear resistance of laser-clad tribaloy T-800 coatings on DD5 single-crystal alloys

In order to enhance the wear resistance of DD5 single-crystal alloys, Tribaloy T-800 wear-resistant coatings were prepared on their surfaces using laser-cladding technology. This study examines the effect of laser energy density on the cracking susceptibility and wear resistance of laser-clad Tribaloy T-800 coatings on DD5 single-crystal alloys. Three distinct laser energy densities (η1=33 J/mm², η2=50 J/mm², η3=60 J/mm²) were applied to create the coatings. The results show that the microstructures of the T-800 laser-clad coatings mainly consist of primary, coarsened, and spheroidized Laves phases, as well as Co-based solid solution and eutectic structures. The phases include Co3Mo2Si phase (Laves phase) and face-centered cubic Co-based solid solution. However, increasing laser energy density enhanced elemental diffusion at the heterogeneous joining interface of the DD5 substrate/T-800 coating, leading to higher Ni content in the coating. This resulted in a reduction in the tendency and content of Mo-rich Laves phase formation respective contents of 53.2 %, 49.2 %, and 47.5 %. Moreover, the decrease in the difference between laser cladding temperature and initial temperature, ∆T, led to reduced thermal stress at the interface, σ, contributing to a decrease in cracking susceptibility (a), with corresponding values of 0.16184, 0.00034, and 0.00022. Thermal expansion coefficients of materials in the cracked region near the interface, measured according to the CALPHAD method, Jmatpro software, and average EDS elemental content data at the crack edge, surpassed those of the corresponding DD5 substrate. Consequently, cracks in the coatings originated from stretching at the interface, with paths tending to cross Laves phase particles in a cleavage mode. The average microhardness of the coatings decreased due to reduced Laves phase content, with values of 783.4 HV0.5, 741.7 HV0.5, and 708.2 HV0.5, respectively, while the fatigue wear of T-800 coatings increased due to exacerbated wear damage from cracking defects. Specifically, average COFs were 0.659, 0.583, and 0.506, with corresponding mass losses of 7.1 mg, 3.4 mg, and 2.9 mg, respectively. The wear mechanisms observed encompassed fatigue wear, abrasive wear, and oxidative wear.

Viscosity Calculation for Al‐Si‐Mg‐Fe System through CALPHAD Method

Viscosity is a crucial parameter affecting the fluidity of metal melts, which directly influences founding properties of Al alloys. However, obtaining viscosity measurement data is difficult for metal melts, and the viscosity prediction for ternary and multi‐component alloys would provide the significant data for selection of process parameters. This study compares the applicability of the Hirai model, SDS model, and R‐K function for viscosity calculations in the sub‐binary systems of Al‐Si‐Mg‐Fe alloys. R‐K function shows the best agreement with experimental data. However, the SDS model shows lower relative error than Hirai model which would play an important role in those system lacking experimental data to predict the viscosities. Ultimately, a database capable of predicting viscosity values for the entire composition and temperature range of the Al‐Si‐Mg‐Fe system was established using the CALPHAD method. Viscosity parameters for Al‐Si, Al‐Mg, Al‐Fe, Mg‐Si, and Mg‐Fe were evaluated and optimized through the R‐K derivation, corroborated with existing experimental data. Using the R‐K function, successful extrapolation and prediction of viscosity for the Al‐Si‐Mg‐Fe ternary and quaternary systems were achieved, with a mean square error between predicted and experimental values of only 0.7%, demonstrating the successful application of the Al‐Si‐Mg‐Fe database for viscosity prediction.This article is protected by copyright. All rights reserved.

Solidification paths of Al-Cu-Sn alloys: Comparison of thermodynamic analyses and solidification experiments using in situ X-radiography

The increasing importance of Al-Cu-Sn alloys as materials for producing self-lubricating bearing materials in automotive industries requires the development of uniform microstructures with improved performance, which could be achieved by a precise control of solidification processes. Adding Sn to Al-Cu binary alloy could dramatically alters the solidification path, generating liquid phase separation and monotectic reaction. In this paper, Al-10 wt% Cu-X wt% Sn (with X = 0; 5; 10 and 20) alloys have their solidification paths investigated by three different complementary approaches. Firstly, the solidification paths were calculated by using the CALPHAD method through Thermo-Calc software revealing the sequence of transformations that could occur during the solidification of these alloys, from the formation of the initial α-Al dendrites to the final eutectic reaction. Secondly, experimental thermal analysis was carried out by DSC (Differential Scanning Calorimetry), which reveals the successive events that occur during the controlled melting and cooling of these alloys. Thirdly, directional solidification was performed on all alloys, with in situ and real-time observations achieved through the utilization of X-radiography. The comparison between the various approaches showed a suitable correspondence between the history of the alloy solidifications computed by Thermo-Calc and those obtained experimentally (DSC and directional solidification experiments). Additional information about the dynamics of each reaction was obtained during the directional solidification experiments in terms of microstructures, segregation, and the genesis of the liquid phase separation that occurred for high Sn-content alloys.

Thermodynamic Simulation Calculations of Phase Transformations in Low-Aluminum Zn-Al-Mg Coatings.

This study delves into the formation, transformation, and impact on coating performance of MgZn2 and Mg2Zn11 phases in low-aluminum Zn-Al-Mg alloy coatings, combining thermodynamic simulation calculations with experimental verification methods. A thermodynamic database for the Zn-Al-Mg ternary system was established using the CALPHAD method, and this alloy's non-equilibrium solidification process was simulated using the Scheil model to predict phase compositions under varying cooling rates and coating thicknesses. The simulation results suggest that the Mg2Zn11 phase might predominate in coatings under simulated production-line conditions. However, experimental results characterized using XRD phase analysis show that the MgZn2 phase is the main phase existing in actual coatings, highlighting the complexity of the non-equilibrium solidification process and the decisive effect of experimental conditions on the final phase composition. Further experiments confirmed that cooling rate and coating thickness significantly influence phase composition, with faster cooling and thinner coatings favoring the formation of the metastable phase MgZn2.

L12 nanoparticle-strengthened CoNi-based superalloy with ultrahigh yield stress developed using CALPHAD method

In this study, a Co-30Ni-10Ti-2Ta-3Al (30Ni3Al) alloy with high γ′ phase dissolution temperature (1215°C), excellent mechanical properties, and low density (8.46 g/cm3) was developed based on the thermodynamic database of Co-based high-temperature alloys established by our group. Compositional design and microstructure control were achieved through the utilization of thermodynamic phase diagrams and phase fractions. It is found that the addition of 2 at.% Ta significantly improves the γ′ phase fraction and solvus while maintaining a suitable working window. However, a rafting trend of γ′ phase was observed as heat treatment for a long time at 750°C. By introducing 3 at.% Al and 30 at.% Ni into the optimized Co-10Ti-2Ta master alloy, the rafting of the γ′ phase was effectively suppressed. Benefiting from the fine, stable, high volume fraction γ′/γ microstructure, the 30Ni3Al alloy demonstrates compressive yield strengths of approximately 1487±7 MPa and 1319±13 MPa at room temperature and 600°C, respectively. The superb mechanical property at high temperatures can be attributed to the work-hardening effect resulting from the interactions of superattice stacking faults in γ′ phase.

Insight into element segregation mechanisms during creep in γʹ-strengthened Co-based superalloy by elastoplastic phase-field simulation

The element segregation accompanying the creep process has been shown to significantly affect the deformation resistance of the superalloys. However, the processing and mechanism of element segregation are still unclear. This paper investigated the concentration evolution of a model Co–9Al–9W (at. %) alloy during 900 ​°C/275 ​MPa using developed ternary elastoplastic phase-field model coupled with CALPHAD method and crystal plasticity model. The results of simulation show that co-depletion of Al and W element occurs in γʹ precipitate and in γ side at γ/γʹ interface, and this depletion is gradually increasing with the accumulation of plastic strain. From the perspective of changes of driving force of element diffusion, it is found that these segregation phenomena are attributed to the high elastic potential caused by the large local plastic strain. In addition, the effects of these segregations on creep property are also predicted. The current research provides a new method for exploring the mechanism of element diffusion.

Thermodynamics assessment of the Erbium-Ruthenium system by combining the Ab-initio and CALPHAD methods

ABSTRACT In the present study, the erbium-ruthenium system was optimised using the CALPHAD approach. The thermodynamic properties and the phase diagram were evaluated. The enthalpies of formation of the intermetallic compounds for the binary system Er-Ru were calculated by ab- initio methods. The liquid phase was treated with the exponential model, while a solution model was applied to represent the HCP (Er, Ru) solid solution. The five intermetallic compounds Er3Ru, Er5Ru2, Er3Ru2, ErRu2, and Er44Ru25 were considered as stoichiometric compounds. The calculations are in good agreement with the phase diagram information and experimental thermodynamic values documented in the literature.