Calphad-computer Coupling of Phase Diagrams and Thermochemistry最新文献

{"title":"Phase relations at 1573 K and 1673 K and thermodynamic assessment of ZrO2-SrO-BaO system","authors":"","doi":"10.1016/j.calphad.2024.102754","DOIUrl":"10.1016/j.calphad.2024.102754","url":null,"abstract":"<div><div>The thermodynamic database of ZrO₂-SrO-BaO system was essential for the development of high-stability refractories. Thirteen samples were prepared using the solid-state reaction method to investigate the isothermal sections of ZrO₂-SrO-BaO system at 1573 K and 1673 K. Four solid solution phases, (Ba, Sr)ZrO₃, (Ba, Sr)₂ZrO₄, (Ba, Sr)₃Zr₂O₇, and (Ba, Sr)₄Zr₃O₁₀, were identified. Based on the re-assessment of SrO-BaO sub-binary system, a self-consistent thermodynamic database of ZrO₂-SrO-BaO system was obtained. Calculated isothermal sections at 1573 K and 1673 K and liquidus projection showed good agreement with existing experimental data. Finally, a potential refractory (Sr_0.06, Ba_0.94)ZrO₃ with better stability was designed using the thermodynamic database of ZrO₂-SrO-BaO system.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic re-assessment of the Al-Li-Zn system","authors":"","doi":"10.1016/j.calphad.2024.102752","DOIUrl":"10.1016/j.calphad.2024.102752","url":null,"abstract":"<div><div>Aluminum-lithium alloys are a kind of highly promising material due to low density, high strength and excellent modulus properties. The proper addition of Zn can effectively promote the precipitation of the main metastable strengthening phase δ′(Al₃Li). As a crucial sub-system of Al-Li alloys, literature data on phase diagram and thermodynamic properties of the Al-Li-Zn system as well as the Al-Li and Li-Zn binary systems were comprehensively evaluated by the CALPHAD approach. The Li-Zn system was reassessed mainly by considering the newly reported data on formation enthalpy and activity and a 2-sublattice (SL) model was applied to describe the βLiZn₄ phase. The Al-Li system was modified by considering AlLi₂ and describing the metastable phase δ′(Al₃Li) with interconvertible 4SL and 2SL ordered-disordered models. The predicted metastable fcc solvus was in perfect agreement with the measurements. Considering the available experimental data, the ternary Al-Li-Zn system was then re-optimized and a self-consistent thermodynamic description of the ternary Al-Li-Zn system was presented. The predicted metastable two-phase region of (Al)+δ’(Al₃Li) in Al-Li-Zn system can be coupled with the accessible experimental data, which can be expected to well assist in designing high-strength Al-Li alloys.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CALPHAD modeling of κ- carbide dual ordering in Fe-Al-C ternary alloys","authors":"","doi":"10.1016/j.calphad.2024.102749","DOIUrl":"10.1016/j.calphad.2024.102749","url":null,"abstract":"<div><div>A novel four-sublattice model for the <span><math><mrow><mi>κ</mi></mrow></math></span> phase, denoted as (Fe, Al)₃(Fe, Al)₁(C, Va)₁(C, Va)₃ was proposed to improve the thermodynamic prediction, such as equilibrium composition, phase stability of <span><math><mrow><mi>κ</mi></mrow></math></span>-carbide in Fe-Al-C system. The sublattice model explains the transformation from the disordered FCC solid solution to the ordered <span><math><mrow><mi>κ</mi></mrow></math></span>-carbide via concurrent ordering of substitutional and interstitial atoms. The dual ordering model can restrict the irregular contribution of configurational entropy arising at 20 at% C composition, which is an issue with the existing thermodynamic databases. For the CALPHAD assessment, <span><math><mrow><mi>κ</mi></mrow></math></span>-carbide was considered as a single, individual phase that is in equilibrium with the liquid, austenite (<span><math><mrow><mi>γ</mi></mrow></math></span>), ferrite (<span><math><mrow><mi>α</mi></mrow></math></span>) or other intermetallic and carbide phases in the Fe-Al-C system. The formation energy calculated from density functional theory (DFT) showed that Fe₃Al–L1₂ phase is energetically more favorable than the Fe₃AlC–E2₁ phase, and C atoms in sublattice <em>IV</em> are not energetically favorable at all. The assessed parameters provided better accuracy than the existing database in the calculations of isothermal sections, liquidus projection, invariant reactions, and low-temperature phase compositions. The model is highly suitable for the low temperature (&lt;800 °C) phase predictions. Thus, the improved Fe-Al-C model lays the foundation for the thermodynamic and kinetic studies of <span><math><mrow><mi>κ</mi></mrow></math></span>-carbide for designing new Fe-Mn-Al-C alloys and optimizing the heat treatment processes.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142357445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modified embedded-atom method interatomic potentials for the V-X (X= Cr, Fe) binary and CoCrFeNiTiV multinary alloys","authors":"","doi":"10.1016/j.calphad.2024.102753","DOIUrl":"10.1016/j.calphad.2024.102753","url":null,"abstract":"<div><div>Interatomic potentials based on the second nearest-neighbor modified embedded-atom method (2NN-MEAM) have been developed for Fe-V and Cr-V binary alloys. The structural, mechanical and thermodynamic properties of various stable and metastable phases in Fe-V and Cr-V binary systems were calculated by molecular dynamic (MD) simulation using the developed 2NN-MEAM potentials. A good consistency between the MD-calculated data and the experimental data or first-principles calculations was obtained. The potentials were further employed to predict several chemically complex intermetallic alloys (CCIAs) with stable B2 and L1₂ ordered structures in CoCrFeNiTiV system. Finally, this work pave the way to investigate the atomic scale physical metallurgy of V-containing and chemically complex intermetallic alloys and adjust their composition and microstructure to meet the specific requirements entailed in advanced applications.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic assessment of the Ce-Rh system by the combination of ab-initio calculations and the CALPHAD approach","authors":"","doi":"10.1016/j.calphad.2024.102747","DOIUrl":"10.1016/j.calphad.2024.102747","url":null,"abstract":"<div><div>The standard enthalpies of formation in this work have been <del>measured</del> calculated by First -principles calculations within DFT (density functional theory) for the metal compounds in the Ce-Rh system. Thermodynamic data and phase diagram information obtained from the literature were used as the input for a CALPHAD-type optimization and Thermo-Calc software of the Ce-Rh.</div><div>The Ce-Rh phase diagram contains seven intermetallic compounds: <span><math><mrow><msub><mrow><mi>C</mi><mi>e</mi></mrow><mn>7</mn></msub><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>3</mn></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>C</mi><mi>e</mi></mrow><mn>5</mn></msub><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>3</mn></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>C</mi><mi>e</mi></mrow><mn>3</mn></msub><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>2</mn></msub></mrow></math></span>, <span><math><mrow><msub><mrow><mi>C</mi><mi>e</mi></mrow><mn>5</mn></msub><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>4</mn></msub></mrow></math></span>, <span><math><mrow><mi>C</mi><mi>e</mi><mi>R</mi><mi>h</mi></mrow></math></span>, <span><math><mrow><mi>C</mi><mi>e</mi><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>2</mn></msub></mrow></math></span> and <span><math><mrow><mi>C</mi><mi>e</mi><msub><mrow><mi>R</mi><mi>h</mi></mrow><mn>3</mn></msub></mrow></math></span>. All these phases were stoichiometric; The associated model concerning the phase equilibria, could accurately describe the full compositional range and the thermodynamic data input with <span><math><mrow><mi>C</mi><mi>e</mi><mi>R</mi><mi>h</mi></mrow></math></span> as associate. The thermodynamic parameters of all intermetallic compounds were modeled by the Neumann-Kopp principle. The value of the temperature-dependent contributions to the individual Gibbs energies was used for all compounds. A fairly good agreement with all values of the enthalpies of formation calculated in this work using the VASP and data available in the literature. ultimately, a set of self-consistent thermodynamic parameters for the Ce-Rh system was obtained.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142323374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Data-driven study of the enthalpy of mixing in the liquid phase","authors":"","doi":"10.1016/j.calphad.2024.102745","DOIUrl":"10.1016/j.calphad.2024.102745","url":null,"abstract":"<div><div>The enthalpy of mixing in the liquid phase is a thermodynamic property reflecting interactions between elements that is key to predict phase transformations. Widely used models exist to predict it, but they have never been systematically evaluated. To address this, we collect a large amount of enthalpy of mixing data in binary liquids from a review of about 1000 thermodynamic evaluations. This allows us to clarify the prediction accuracy of Miedema's model which is state-of-the-art. We show that more accurate predictions can be obtained from a machine learning model based on LightGBM, and we provide them in 2415 binary systems. The data we collect also allows us to evaluate another empirical model to predict the excess heat capacity that we apply to 2211 binary liquids. We then extend the data collection to ternary metallic liquids and find that, when mixing is exothermic, extrapolations from the binary systems by Muggianu's model systematically lead to slight overestimations of roughly 10 % close to the equimolar composition. Therefore, our LightGBM model can provide reasonable estimates for ternary alloys and, by extension, for multicomponent alloys. Our findings extracted from rich datasets can be used to feed thermodynamic, empirical and machine learning models for material development. Our data, predictions, and code to generate machine learning descriptors from thermodynamic properties are all made available.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0364591624000877/pdfft?md5=df19fdf9c38bb676b03998398a380d44&pid=1-s2.0-S0364591624000877-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142314923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vaporisation thermodynamic studies over <U3Sn7(cr) + USn2(cr)> and <USn2(cr) + USn(cr)> biphasic regions of U-Sn system using high temperature mass spectrometry","authors":"","doi":"10.1016/j.calphad.2024.102751","DOIUrl":"10.1016/j.calphad.2024.102751","url":null,"abstract":"<div><div>High-temperature vaporisation thermodynamic studies over &lt;U₃Sn₇(cr) + USn₂(cr)&gt; and &lt;USn₂(cr) + USn(cr)&gt; two-phase regions were carried out by employing Knudsen Effusion Mass Spectrometry (KEMS) in the temperature range 1148–1465 and 1222–1471 K, respectively. Sn(g) was the only species observed in the mass spectra of the equilibrium vapour phase over both the biphasic regions. The partial pressure-temperature relations of Sn(g) were deduced as</div><div>log(p_Sn/Pa) = (−15,737 ± 73)/(T/K)) + (9.52 ± 0.06) (1148–1465 K) &lt;U₃Sn₇(cr) + USn₂(cr)&gt; and</div><div>log(p_Sn/Pa) = (−16,151 ± 67)/(T/K)) + (9.70 ± 0.05) (1222–1471 K) &lt;USn₂(cr) + USn(cr)&gt;</div><div>Using p-T relations, the enthalpies of the following heterogeneous reaction equilibria were evaluated by the second law method: U₃Sn₇(cr) = 3USn₂(cr) + Sn(g) and USn₂(cr) = USn(cr) + Sn(g). Subsequently, the Gibbs energies of the formation of U₃Sn₇(cr) and USn₂(cr) were derived. Knudsen effusion mass spectrometric studies over these two biphasic regions are being reported for the first time.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142314922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic coupling and interfacial non-equilibrium in a finite-diffusion model of microsegregation","authors":"","doi":"10.1016/j.calphad.2024.102744","DOIUrl":"10.1016/j.calphad.2024.102744","url":null,"abstract":"<div><div>We introduce both CALPHAD coupling and interfacial non-equilibrium to a model of microsegregation that accounts for finite diffusion. The approach can also be used to perform Gulliver–Scheil calculations using a kinetic phase diagram, which would normally involve solving an underdetermined system of equations. The non-equilibrium finite-diffusion model is first applied to the Ag–15wt.%Cu system, where we find that previously reported experimental measurements can be completely described with the full non-linear phase diagram and the choice of appropriate kinetic constitutive parameters, indicating that the effects of finite liquid diffusion remain significant under processing conditions relevant to additive manufacturing. The model is enhanced to account for multiple phases forming from the liquid and then applied to a multicomponent Co-base superalloy, showing that finite liquid diffusion can influence both the compositions and fractions of secondary solid phases.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142314921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic modeling of phase diagrams in La2O3-SiO2, Dy2O3-SiO2 and Er2O3-SiO2 systems","authors":"","doi":"10.1016/j.calphad.2024.102750","DOIUrl":"10.1016/j.calphad.2024.102750","url":null,"abstract":"<div><p>Thermodynamic modeling of the La₂O₃-SiO₂, Dy₂O₃-SiO₂ and Er₂O₃-SiO₂ systems is part of a broader effort to obtain thermodynamic databases of the rare earth silicates that can help offer insight on designing the environmental barrier coatings in gas turbine engines. The main aim of the present work is to focus on obtaining a set of self-consistent thermodynamic parameters of La₂O₃-SiO₂, Dy₂O₃-SiO₂ and Er₂O₃-SiO₂ systems. The ionic two-sublattice model was accepted to express the liquid phase, and all the binary phases were described as stoichiometric compounds due to the negligible solubility. After a critical literature review on the experimental phase diagrams data and thermodynamic properties for the La₂O₃-SiO₂, Dy₂O₃-SiO₂ and Er₂O₃-SiO₂ systems, thermodynamic optimizations were performed by means of the CALPHAD (CALculation of PHAse Diagram) method. The modeling was done using Thermo-Calc software with PARROT module. The comprehensive comparison between the experimental results and our calculations exhibits that the calculated phase diagrams and thermodynamic properties were in good agreement with the available experimental data, except for experimental data with doubtful quality. This means that our thermodynamic descriptions were reasonable and could provide a reliable basis for thermodynamic calculations in RE₂O₃-SiO₂-based higher-order systems.</p></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Classified dataset, regression and machine learning modeling for prediction of phase transformation temperatures in steels","authors":"","doi":"10.1016/j.calphad.2024.102748","DOIUrl":"10.1016/j.calphad.2024.102748","url":null,"abstract":"<div><p>The prediction of the characteristic Martensite Start (<em>M</em>_<em>s</em>) temperature and Austenitic Nose Tip Temperature (ANTT) in steels is of scientific and technological importance; however, it faces significant challenges due to multiphysical complexity.</p><p>In this study, we introduced a structured framework for data classification and hierarchical iterations aimed at predicting Ms (Martensite start temperature) and ANTT (Austenite non-transforming temperature). This framework was incorporated into two optimization models, leading to enhancements in accuracy, extrapolation capabilities, and generalization performance. First, we classified the collected Ms datasets hierarchically based on the alloying elements presented in steels, including carbon, austenite stabilizers, non-austenitization elements, and data credibility. Regression analyses of Ms temperatures concerning chemical compositions were then carried out using phenomenological variables from binary systems to multi-component systems in alignment with the spirit of CALPHAD modeling, which is renowned for its robust extrapolation abilities. By iteratively fitting the hierarchically classified datasets and implementing hierarchical iterations, we developed the CALPHAD-guided phenomenological variable (CGPV) Ms regression model. This model achieved improved accuracy levels, with R² values of 0.9 for training and 0.87 for testing, surpassing most conventional regression models that do not account for compositional interactions. Furthermore, the CALPHAD-guided machine learning (CGML) model, constructed based on the classified datasets and hierarchical iterations but without utilizing phenomenological variables, demonstrated strong performance with R² values of 0.98 and 0.86 for training and testing, respectively. The CGML model was demonstrated not only to reliably filter out problematic data in a dataset but also to unveil the unnoticed coupling between carbon and other alloying elements on <em>M</em>_<em>s</em>. Finally, the CGML method has been readily transferred to predict ANTT with high accuracy as well.</p></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142243909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}