{"title":"Assessed uncertainty in the Ti-W phase diagram combining experimental and ab-initio data","authors":"Tobias Spitaler, Lorenz Romaner","doi":"10.1016/j.calphad.2025.102872","DOIUrl":"10.1016/j.calphad.2025.102872","url":null,"abstract":"<div><div>The binary Ti-W system is reassessed with uncertainty quantification using the open source software ESPEI (Extensible, Self-optimizing Phase Equilibria Infrastructure). Mixing energy data at 0<!--> <!-->K from ab-initio are used to supplement the phase diagram data measured at 1373<!--> <!-->K and above. For the parameter optimization, Bayesian Inference with Markov Chain Monte Carlo is used as implemented in ESPEI, which allows for an inherent uncertainty quantification of the model parameters and a propagation of the uncertainty to the phase diagram, mixing enthalpy, and the position of invariant points. The new phase diagram shows a higher solubility of Ti in BCC_A2 W at low temperatures compared to older phase diagrams obtained from phase diagram data only.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102872"},"PeriodicalIF":1.9,"publicationDate":"2025-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155691","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}
Juan Chen , Zhanqi E , Na Ta , Jinkun Xiao , Lijun Zhang
{"title":"Diffusion study between NiCrFe alloy and high entropy alloys","authors":"Juan Chen , Zhanqi E , Na Ta , Jinkun Xiao , Lijun Zhang","doi":"10.1016/j.calphad.2025.102882","DOIUrl":"10.1016/j.calphad.2025.102882","url":null,"abstract":"<div><div>The diffusion couples composed of NiCrFe (Ni-21 at% Cr-9 at% Fe) alloy and three kinds of high entropy alloys (CoCrFeMn<sub>0.2</sub>Ni, Al<sub>x</sub>CoCrFeNi (x = 0.2 or 0.3), and CoCrCu<sub>0.2</sub>FeNi HEAs) were fabricated, and subjected to diffusion annealing at 1273, 1323, and 1373 K, respectively. The interdiffusion coefficients were calculated using electron probe technology and <strong>Hi</strong>gh-<strong>t</strong>hroughput <strong>D</strong>etermination of <strong>I</strong>nterdiffusion <strong>C</strong>oefficients (HitDIC) software, and their reliability was validated. The interdiffusion coefficients increase as the temperature increase. The diffusion coefficients of Mn, Al, and Cu atoms on HEAs side in all diffusion couples are higher than those of Fe, Co, and Ni in the corresponding diffusion couples, and Al has the lower diffusion coefficient than Co, Cr, and Fe on NiCrFe side in Al<sub>x</sub>CoCrFeNi/NiCrFe diffusion couples. Furthermore, based on the interdiffusion coefficients at three different temperatures, the diffusion activation energies of atoms were also analyzed.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102882"},"PeriodicalIF":1.9,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155690","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":"Experimental study and thermodynamic assessment of the MgO-Al2O3-P2O5 system","authors":"Caisheng Guo , Fengyang Gao , Caicai Zhang , Tengfei Deng","doi":"10.1016/j.calphad.2025.102883","DOIUrl":"10.1016/j.calphad.2025.102883","url":null,"abstract":"<div><div>The phase relationships of the MgO-Al<sub>2</sub>O<sub>3</sub>-P<sub>2</sub>O<sub>5</sub> system at 1473 K was determined using the quenching method. The ternary compound MgAl(PO<sub>4</sub>)O was considered in this study, which had not been addressed in previous reports. The phase diagram of the MgO-Al<sub>2</sub>O<sub>3</sub>-P<sub>2</sub>O<sub>5</sub> system was thermodynamically assessed using the CALculation of PHAse Diagram (CALPHAD) method with Thermo-Calc software, incorporating both the experimental data from this study and existing literature data. An ionic two-sublattice model, (Mg<sup>+2</sup>, Al<sup>+3</sup>)<sub>P</sub>(O<sup>−2</sup>,AlO<sub>2</sub><sup>−1</sup>,PO<sub>4</sub><sup>−3</sup>,PO<sub>7/2</sub><sup>−2</sup>,PO<sub>3</sub><sup>−1</sup>,PO<sub>5/2</sub>)<sub>Q</sub> was used to described the liquid phase of the MgO-Al<sub>2</sub>O<sub>3</sub>-P<sub>2</sub>O<sub>5</sub> system. The excess Gibbs energy was formulated by the Redlich-Kister expression. All solid intermediate compounds containing phosphorus were treated as stoichiometric compounds. The Gibbs energy of intermediate compounds could be modeled following Neumann-Kopp's rule. A set of self-consistent thermodynamic parameters for the MgO-Al<sub>2</sub>O<sub>3</sub>-P<sub>2</sub>O<sub>5</sub> system was obtained and the calculated phase diagrams were in good agreement with the experimental data. This work contributes to the construction of the database for high-order systems, thereby facilitating the synthesis of phosphorus-containing materials.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102883"},"PeriodicalIF":1.9,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155689","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}
Haoran Wang , Fengqi Zhou , Tongsheng Zhang , Yusheng Hu , Jian Yang , Zushu Li
{"title":"Thermodynamic assessment of CaO-Al2O3-SiO2-Ce2O3 subsystems","authors":"Haoran Wang , Fengqi Zhou , Tongsheng Zhang , Yusheng Hu , Jian Yang , Zushu Li","doi":"10.1016/j.calphad.2025.102884","DOIUrl":"10.1016/j.calphad.2025.102884","url":null,"abstract":"<div><div>To guide the production of rare earth steels and optimization of recycling processes for rare earth solid wastes, the thermodynamic properties of related rare earth oxides containing systems need to be understood. However, only limited thermodynamic data are currently available for such slag systems. Based on the existing experimental data as well as thermodynamic data, thermodynamic descriptions of CaO-SiO<sub>2</sub>-Ce<sub>2</sub>O<sub>3</sub>, CaO-Al<sub>2</sub>O<sub>3</sub>-Ce<sub>2</sub>O<sub>3</sub>, Al<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub>-Ce<sub>2</sub>O<sub>3</sub> ternary system and Ce<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub> binary system were constructed in current work. The Gibbs energy of liquid slag was modeled by using the Modified Quasichemical Model, and the excess Gibbs energy of solid phases were described with polynomial expansions. The optimized phase diagrams are in good agreement with the experimental data in previous researches.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102884"},"PeriodicalIF":1.9,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119041","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}
Hantong Chen , Qi-Jun Hong , Alexandra Navrotsky , Axel van de Walle
{"title":"A computational free energy reference for mechanically unstable phases","authors":"Hantong Chen , Qi-Jun Hong , Alexandra Navrotsky , Axel van de Walle","doi":"10.1016/j.calphad.2025.102869","DOIUrl":"10.1016/j.calphad.2025.102869","url":null,"abstract":"<div><div>The CALPHAD (CALculation of PHAse Diagram) framework relies heavily on the availability of a well-defined free energy for all possible phases, including metastable and even mechanically unstable phases. However, for phases that exhibit mechanical instability, the determination of the free energy represents a challenge, both experimentally and computationally. This situation hinders the seamless integration of experimental and ab initio thermodynamic data. A newly developed method, named “inflection-detection”, provides a practical computational solution to this problem with a sound theoretical basis. Extending upon existing energy calculations at absolute zero, we provide further evidence of this method’s effectiveness by computing the temperature-dependent free energy references for 22 elemental structures involving mechanically unstable phases and showing that they are reasonably consistent with the (often wide) range of values determined in earlier experimental assessments. This suggests the feasibility of a reliable computation-based reference free energy standard for mechanically unstable pure elements.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102869"},"PeriodicalIF":1.9,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145060883","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 description of aluminum -cadmium-magnesium system","authors":"Daiman Zhu , Xiaohan Liu , Nele Moelans","doi":"10.1016/j.calphad.2025.102881","DOIUrl":"10.1016/j.calphad.2025.102881","url":null,"abstract":"<div><div>A thermodynamic description of the Al-Cd-Mg ternary system has been developed using the CALPHAD (CALculation of PHAse Diagrams) approach, based on critical assessment of the three constituent binary systems: Al-Cd, Al-Mg, and Cd-Mg, and considering available experimental data and information on phase equilibria, crystallography, and constitutional information from literature. The solution phases, liquid, Hcp_A3 and Fcc_A1, are modeled using the Redlich-Kister formalism. Ternary solubilities of the binary phases Al<sub>3</sub>Mg<sub>2</sub>, Al<sub>12</sub>Mg<sub>17</sub>, Al<sub>30</sub>Mg<sub>23</sub> and of the binary ordered phases, Cd<sub>3</sub>Mg, CdMg and CdMg<sub>3</sub>, are included. Comparisons between calculated results and experimental data for the liquidus projection and two isothermal sections demonstrate good agreement, confirming that the proposed thermodynamic model reliably reproduces the phase equilibria of the Al-Cd-Mg system. A consistent set of thermodynamic parameters has thus been obtained for application in computation assisted Al-Cd-Mg alloy design.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102881"},"PeriodicalIF":1.9,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046915","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}
Xiaoshu Wang , Ning Wang , Fupeng Liu , Jinfa Liao , Baojun Zhao
{"title":"Application and evaluation of thermodynamic modeling on phase equilibria of the CaO–MgO–SiO2–Al2O3–TiO2 system","authors":"Xiaoshu Wang , Ning Wang , Fupeng Liu , Jinfa Liao , Baojun Zhao","doi":"10.1016/j.calphad.2025.102880","DOIUrl":"10.1016/j.calphad.2025.102880","url":null,"abstract":"<div><div>Vanadium titanomagnetite (VTM) is a polymetallic ore of significant industrial value, serving as a primary source for iron and vanadium production through high-temperature processes like blast furnace operations. During smelting, the residual components from VTM and flux combine to form CaO-MgO-Al<sub>2</sub>O<sub>3</sub>-SiO<sub>2</sub>-TiO<sub>2</sub> slag systems. Accurate determination of slag liquidus temperatures is crucial for optimizing process parameters in industrial applications. This study employs thermodynamic modeling (FactSage) alongside experimental validation to investigate these properties. The experimental approach involves high-temperature equilibration, rapid quenching, and phase composition analysis using electron probe X-ray microanalysis (EPMA). The results provide critical validation of FactSage predictions regarding liquidus temperatures and solid solution formations in the slag system. These findings offer practical guidance for researchers and blast furnace operators in effectively utilizing FactSage for slag property simulations under operational conditions. Furthermore, the study demonstrates the application of pseudo-binary phase diagrams for slag composition optimization.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102880"},"PeriodicalIF":1.9,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046913","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}
Sang-Ho Oh , MinAh Baek , Jaemin Wang , Seughyo Noh , Minwoo Kang , Jihye Park , Do Sung Lee , Young-Su Lee , Taewook Na , Byeong-Joo Lee
{"title":"Thermodynamic modeling of hydrogenation of C14 TiMnx alloys","authors":"Sang-Ho Oh , MinAh Baek , Jaemin Wang , Seughyo Noh , Minwoo Kang , Jihye Park , Do Sung Lee , Young-Su Lee , Taewook Na , Byeong-Joo Lee","doi":"10.1016/j.calphad.2025.102871","DOIUrl":"10.1016/j.calphad.2025.102871","url":null,"abstract":"<div><div>C14 TiMn<sub>x</sub>-type alloys are promising hydrogen storage materials. However, their thermodynamic properties during hydrogenation cannot be easily predicted since their thermodynamics has not been modeled. Here, we present a CALPHAD-type thermodynamic description of the C14 TiMn<sub>2</sub>-H system. A sublattice model, [Mn,Ti]<sub>2</sub>[Mn,Ti]<sub>1</sub>[H,Va]<sub>3</sub>, was adopted for the C14 phase according to a first-principles calculation, and thermodynamic parameters were assessed using experimental pressure-composition-temperature data. The assessed thermodynamic parameter set reproduces the experimental pressure-composition-temperature data of C14 phases across different compositions. The present work provides a basis for thermodynamic modeling of hydrogenation in multicomponent C14 alloys and will contribute to the efficient design of hydrogen storage materials based on C14 alloys.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"91 ","pages":"Article 102871"},"PeriodicalIF":1.9,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144989560","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":"Summary report of CALPHAD LI –Mannheim, Germany, May 2024","authors":"Hans Jürgen Seifert , Andre Schneider","doi":"10.1016/j.calphad.2025.102862","DOIUrl":"10.1016/j.calphad.2025.102862","url":null,"abstract":"<div><div>The CALPHAD LI 2024 conference was held in Mannheim, Germany from May 26 to May 31, 2024. We had 203 attendees from 25 countries. The activities in CALPHAD LI included 81 oral presentations, 95 posters, and three software workshops. The topics covered during the conference were gathered in 12 categories.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"90 ","pages":"Article 102862"},"PeriodicalIF":1.9,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145004017","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 reassessment of the Fe–Pt system","authors":"Marino Tanaka , Mayu Muramatsu , Machiko Ode , Taichi Abe","doi":"10.1016/j.calphad.2025.102868","DOIUrl":"10.1016/j.calphad.2025.102868","url":null,"abstract":"<div><div>In this study, the Fe–Pt binary system was critically reassessed by means of the CALPHAD technique for the applications of the next-generation data storage media. The liquid and A2 phases were modeled as substitutional solutions. The fcc-based phases (L1<sub>2</sub>–Fe<sub>3</sub>Pt, L1<sub>0</sub>–FePt, L1<sub>2</sub>–FePt<sub>3,</sub> and A1) were modeled using the split-compound energy formalism (split-CEF) with four sublattices, where the effect of short-range ordering was taken into account through the reciprocal parameters. The formation enthalpies of the fcc-based phases were reproduced well by introducing the regular terms that represent the second-nearest-neighbor interactions in the fcc lattice. The magnetic excess Gibbs energies described by the Inden model were assessed for the fcc-based ordered and disordered phases. The obtained parameter set in the present work can reproduce satisfactorily the key theoretical and experimental data in this system.</div></div>","PeriodicalId":9436,"journal":{"name":"Calphad-computer Coupling of Phase Diagrams and Thermochemistry","volume":"90 ","pages":"Article 102868"},"PeriodicalIF":1.9,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144916417","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}