Pub Date : 2025-12-15DOI: 10.1016/j.commatsci.2025.114449
Mehady Hassan , Mohammad Jane Alam Khan
The thermal stability, excellent mechanical property, and low cost marks VNbTaTiZr refractory high-entropy alloy (RHEA) as a favorable material for applications in extreme conditions. However, its deformation behavior under high strain rates is mostly unexplored. This study performs non-equilibrium molecular dynamics (NEMD) simulations to investigate the dynamic shock response of VNbTaTiZr RHEA. Three crystallographic directions [0 0 1], [1 1 0], and [1 1 1], are analyzed for different piston velocities and temperatures in the range of 0.4–1.6 km/s and 100–1200 K, respectively. We have observed that shock response depends strongly on shock direction and strength, and temperature. Deformation modes are found to be as dislocation slip, twinning, and phase transformations. [1 1 0] direction has the highest dislocation activity while [0 0 1] direction demonstrates highest spall strength and resistance to plastic flow. [1 1 1] direction shows some delay in the onset of plastic flow and has the lowest elastic stability and spall strength. Shock properties, i.e., Hugoniot elastic limit (HEL), Hugoniot stress, and shock velocity increases and spall strength decreases with increasing piston velocity. All the shock properties decrease with increasing initial temperature due to thermal softening. Hugoniot stress is comparable while shear stress varies in different shock directions, indicating isotropic equilibrium shock response and anisotropic deformation mechanisms. These findings are crucial for optimizing VNbTiTaZr for high temperature and high strain rate applications.
{"title":"Atomistic analysis of dynamic shock compression behavior of VNbTiTaZr refractory high-entropy alloy","authors":"Mehady Hassan , Mohammad Jane Alam Khan","doi":"10.1016/j.commatsci.2025.114449","DOIUrl":"10.1016/j.commatsci.2025.114449","url":null,"abstract":"<div><div>The thermal stability, excellent mechanical property, and low cost marks VNbTaTiZr refractory high-entropy alloy (RHEA) as a favorable material for applications in extreme conditions. However, its deformation behavior under high strain rates is mostly unexplored. This study performs non-equilibrium molecular dynamics (NEMD) simulations to investigate the dynamic shock response of VNbTaTiZr RHEA. Three crystallographic directions [0 0 1], [1 1 0], and [1 1 1], are analyzed for different piston velocities and temperatures in the range of 0.4–1.6 km/s and 100–1200 K, respectively. We have observed that shock response depends strongly on shock direction and strength, and temperature. Deformation modes are found to be as dislocation slip, twinning, and phase transformations. [1 1 0] direction has the highest dislocation activity while [0 0 1] direction demonstrates highest spall strength and resistance to plastic flow. [1 1 1] direction shows some delay in the onset of plastic flow and has the lowest elastic stability and spall strength. Shock properties, i.e., Hugoniot elastic limit (HEL), Hugoniot stress, and shock velocity increases and spall strength decreases with increasing piston velocity. All the shock properties decrease with increasing initial temperature due to thermal softening. Hugoniot stress is comparable while shear stress varies in different shock directions, indicating isotropic equilibrium shock response and anisotropic deformation mechanisms. These findings are crucial for optimizing VNbTiTaZr for high temperature and high strain rate applications.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114449"},"PeriodicalIF":3.3,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787007","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}
Pub Date : 2025-12-15DOI: 10.1016/j.commatsci.2025.114450
Xitian Ou, Zhipeng Pi, Donglin Li, Sifeng Huang, Fan Zhang
This study proposes a unified multiphysics phase-field model to simulate the microstructural evolution in Al–Mg alloys, which involves two stages: first, the precipitation of the phase (-AlMg) from the phase (FCC Al), and second, the twinning deformation within the phase after its growth to a critical size. This model integrates the CALPHAD thermodynamic database and fully considers the effects of anisotropic interface energies, including the phase boundary and the twin boundaries, as well as the heterogeneous effects arising from the elastic misfit between the precipitate and matrix phases. Based on this, the KKS model is employed to model the - phase transformation; the deformation twinning phase field model is employed to describe the twinning process; two models are weakly coupled to reproduce the twinned precipitate microstructure. The simulated results are in excellent agreement with experimental data, validating the model’s effectiveness in characterizing the complex microstructural evolution of this type of alloy. The findings indicate that the nucleation and evolution of twinning in precipitates, a process limited by precipitate size, follow the Hall–Petch relation, providing a new theoretical framework for understanding phase transformation behaviors in Al–Mg alloys and their impact on material properties.
{"title":"Unveiling the twinning and evolution of β precipitates in Al–Mg alloys: A phase field model","authors":"Xitian Ou, Zhipeng Pi, Donglin Li, Sifeng Huang, Fan Zhang","doi":"10.1016/j.commatsci.2025.114450","DOIUrl":"10.1016/j.commatsci.2025.114450","url":null,"abstract":"<div><div>This study proposes a unified multiphysics phase-field model to simulate the microstructural evolution in Al–Mg alloys, which involves two stages: first, the precipitation of the <span><math><mi>β</mi></math></span> phase (<span><math><mi>β</mi></math></span>-Al<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>Mg<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>) from the <span><math><mi>α</mi></math></span> phase (FCC Al), and second, the twinning deformation within the <span><math><mi>β</mi></math></span> phase after its growth to a critical size. This model integrates the CALPHAD thermodynamic database and fully considers the effects of anisotropic interface energies, including the <span><math><mrow><mi>α</mi><mo>/</mo><mi>β</mi></mrow></math></span> phase boundary and the twin boundaries, as well as the heterogeneous effects arising from the elastic misfit between the precipitate and matrix phases. Based on this, the KKS model is employed to model the <span><math><mi>α</mi></math></span>-<span><math><mi>β</mi></math></span> phase transformation; the deformation twinning phase field model is employed to describe the twinning process; two models are weakly coupled to reproduce the twinned precipitate microstructure. The simulated results are in excellent agreement with experimental data, validating the model’s effectiveness in characterizing the complex microstructural evolution of this type of alloy. The findings indicate that the nucleation and evolution of twinning in precipitates, a process limited by precipitate size, follow the Hall–Petch relation, providing a new theoretical framework for understanding phase transformation behaviors in Al–Mg alloys and their impact on material properties.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114450"},"PeriodicalIF":3.3,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787105","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}
Superhard ceramics are suitable materials to improve the surface characteristics of titanium. In this study, TiB2 nanopowder was coated on titanium substrate using electrophoretic deposition in NaF-AlF3-Al2O3 molten salts. The effects of varying deposition voltages and deposition times on TiB2 coatings were investigated. Additionally, the microstructure of the coating surface was observed by scanning electron microscopy. With an applied cell voltage of 1.2 V and a deposition time of 1.5 h, a dense, defect-free TiB2/TiB composite coating (including the outer TiB2 layer and the inner TiB whiskers layer) approximately 74 μm thick was produced, exhibiting a strong metallurgical bond to the substrate. A densely packed TiB whisker layer forms at the TiB2/Ti interface. The work of adhesion, interfacial energy, and electronic structure of the α-Ti(0001)/TiB2(0001) interfaces have been calculated using first-principles methods. Simultaneously, the diffusion of B atoms at the TiB2/Ti interface was computed to explain the formation process of TiB whisker layers. The work of adhesion calculations indicated that the B-HCP-Ti interfacial model exhibited the highest interfacial bond strength. The electronic structure of the interfacial model was analyzed to show that the Ti-terminated interface model was primarily formed through metallic bonds, while the B-terminated interface model was primarily formed through covalent bonds. Compared to the Ti-terminated interface, the B-terminated interface facilitates the diffusion of boron from TiB2 into the titanium substrate more effectively.
{"title":"Interfacial bonding mechanisms in TiB2/Ti systems fabricated by molten salt electrophoretic deposition: Experimental and first-principles calculation","authors":"Peipei Liu, Chunchun Dong, Xiping Chen, Xuemin Liang","doi":"10.1016/j.commatsci.2025.114445","DOIUrl":"10.1016/j.commatsci.2025.114445","url":null,"abstract":"<div><div>Superhard ceramics are suitable materials to improve the surface characteristics of titanium. In this study, TiB<sub>2</sub> nanopowder was coated on titanium substrate using electrophoretic deposition in NaF-AlF<sub>3</sub>-Al<sub>2</sub>O<sub>3</sub> molten salts. The effects of varying deposition voltages and deposition times on TiB<sub>2</sub> coatings were investigated. Additionally, the microstructure of the coating surface was observed by scanning electron microscopy. With an applied cell voltage of 1.2 V and a deposition time of 1.5 h, a dense, defect-free TiB<sub>2</sub>/TiB composite coating (including the outer TiB<sub>2</sub> layer and the inner TiB whiskers layer) approximately 74 μm thick was produced, exhibiting a strong metallurgical bond to the substrate. A densely packed TiB whisker layer forms at the TiB<sub>2</sub>/Ti interface. The work of adhesion, interfacial energy, and electronic structure of the α-Ti(0001)/TiB<sub>2</sub>(0001) interfaces have been calculated using first-principles methods. Simultaneously, the diffusion of B atoms at the TiB<sub>2</sub>/Ti interface was computed to explain the formation process of TiB whisker layers. The work of adhesion calculations indicated that the B-HCP-Ti interfacial model exhibited the highest interfacial bond strength. The electronic structure of the interfacial model was analyzed to show that the Ti-terminated interface model was primarily formed through metallic bonds, while the B-terminated interface model was primarily formed through covalent bonds. Compared to the Ti-terminated interface, the B-terminated interface facilitates the diffusion of boron from TiB<sub>2</sub> into the titanium substrate more effectively.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114445"},"PeriodicalIF":3.3,"publicationDate":"2025-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145787006","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}
Pub Date : 2025-12-13DOI: 10.1016/j.commatsci.2025.114442
Zihao Zhao , Mingwei Li , Ping Wu , Zijie Huang , Ying Zhang , Min Huang
The atomic structures, stability and magnetic properties of small Con (n = 1–6) clusters on Al-doped Cu(111) surface were investigated by means of Density Functional Theory calculations (DFT + U) and ab initio molecular dynamics (AIMD). Our calculation results indicate that the supported clusters considered are all in two-dimensional structures, which show high stability at temperature up to 600 K evidenced by our AIMD simulations. Furthermore, the relative stability of small Co clusters on Al-doped Cu(111) surface enhances with the increasing of cluster size. Therefore, 1 monolayer (ML) Co film show high stability on Al-doped Cu(111) surface, which is in agreement with experimental observations and high quality Co film may be deposited on Al-doped Cu(111) surface for device applications. Our calculation suggests that AlCu alloy buffer layer only have significant effects on Co film growth at initial stage since the adsorption sites for Con (n = 1–5) clusters are different on Al-doped Cu(111) surface (bridge site of two neighboring surface Al atoms) and Cu(111) pristine surface (hcp hollow site), and the adsorption sites of Con (n = 6–13) clusters become the same on both surfaces. All the considered systems of Al-doped Cu(111) surface with Con cluster adsorbed show ferromagnetic ground states with high magnetic moments and the spin density distributions mainly origin from Con clusters and surface Cu and Al atoms have very minor contributions. Co ML film on Al-doped Cu(111) surface exhibits preference of in-plane magnetization, which agrees the behavior of Co films on Cu(111) surface prepared by pulsed laser ablation. Our study can provide basic information of the initial stages of Co film growth and nucleation on Al-doped Cu(111) substrate at atomic level and may shed light on Co/Al-Cu(111) system being potential applications in spintronic devices.
{"title":"Structures, stability and magnetic properties of small cobalt clusters on Al-doped Cu(111) surface: A DFT + U study","authors":"Zihao Zhao , Mingwei Li , Ping Wu , Zijie Huang , Ying Zhang , Min Huang","doi":"10.1016/j.commatsci.2025.114442","DOIUrl":"10.1016/j.commatsci.2025.114442","url":null,"abstract":"<div><div>The atomic structures, stability and magnetic properties of small Co<sub>n</sub> (<em>n</em> = 1–6) clusters on Al-doped Cu(111) surface were investigated by means of Density Functional Theory calculations (DFT + U) and <em>ab initio</em> molecular dynamics (AIMD). Our calculation results indicate that the supported clusters considered are all in two-dimensional structures, which show high stability at temperature up to 600 K evidenced by our AIMD simulations. Furthermore, the relative stability of small Co clusters on Al-doped Cu(111) surface enhances with the increasing of cluster size. Therefore, 1 monolayer (ML) Co film show high stability on Al-doped Cu(111) surface, which is in agreement with experimental observations and high quality Co film may be deposited on Al-doped Cu(111) surface for device applications. Our calculation suggests that Al<img>Cu alloy buffer layer only have significant effects on Co film growth at initial stage since the adsorption sites for Co<sub>n</sub> (<em>n</em> = 1–5) clusters are different on Al-doped Cu(111) surface (bridge site of two neighboring surface Al atoms) and Cu(111) pristine surface (<em>hcp</em> hollow site), and the adsorption sites of Co<sub>n</sub> (<em>n</em> = 6–13) clusters become the same on both surfaces. All the considered systems of Al-doped Cu(111) surface with Co<sub>n</sub> cluster adsorbed show ferromagnetic ground states with high magnetic moments and the spin density distributions mainly origin from Co<sub>n</sub> clusters and surface Cu and Al atoms have very minor contributions. Co ML film on Al-doped Cu(111) surface exhibits preference of in-plane magnetization, which agrees the behavior of Co films on Cu(111) surface prepared by pulsed laser ablation. Our study can provide basic information of the initial stages of Co film growth and nucleation on Al-doped Cu(111) substrate at atomic level and may shed light on Co/Al-Cu(111) system being potential applications in spintronic devices.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114442"},"PeriodicalIF":3.3,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733904","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}
Pub Date : 2025-12-13DOI: 10.1016/j.commatsci.2025.114435
Daqi Yuan , Tingting He , Hongxian Xie , Huigang Shi , Xianglong Guo , Guang-Hong Lu
The migration of Σ3{112} incoherent twin boundary (ITB) in nanotwinned face-centered cubic metals/alloys can lead to twinning or detwinning, thereby significantly influencing the stability of the nanotwinned structure; however, the effect of radiation-induced defects on the migration of the ITB is not fully understood and needs further investigation. In the present study, the effect of vacancies and interstitials on the migration of the ITB in Cu was systematically studied by molecular dynamic simulation method. The simulation results revealed that vacancies/interstitials have double-fold effect on the migration of the ITB: resistance effect works during absorption process of vacancies/interstitials into the ITB, while the absorbed vacancies/interstitials can accelerate rather than retard the migration of the ITB. Importantly, the resistance effect plays a dominant role, thus the migration of ITB can be retarded by radiation-induced defects. Furthermore, the underlying mechanism of the double-fold effect was discussed that cross-layer rearrangement of vacancies in the ITB is prevailing in retarded effect on the ITB migration. The present work gives a deeper insight into the effect of radiation-induced defects on the migration of ITB.
{"title":"Double-fold effect of vacancies and interstitials on the migration of Σ3{112} incoherent twin boundary in copper","authors":"Daqi Yuan , Tingting He , Hongxian Xie , Huigang Shi , Xianglong Guo , Guang-Hong Lu","doi":"10.1016/j.commatsci.2025.114435","DOIUrl":"10.1016/j.commatsci.2025.114435","url":null,"abstract":"<div><div>The migration of Σ3{112} incoherent twin boundary (ITB) in nanotwinned face-centered cubic metals/alloys can lead to twinning or detwinning, thereby significantly influencing the stability of the nanotwinned structure; however, the effect of radiation-induced defects on the migration of the ITB is not fully understood and needs further investigation. In the present study, the effect of vacancies and interstitials on the migration of the ITB in Cu was systematically studied by molecular dynamic simulation method. The simulation results revealed that vacancies/interstitials have double-fold effect on the migration of the ITB: resistance effect works during absorption process of vacancies/interstitials into the ITB, while the absorbed vacancies/interstitials can accelerate rather than retard the migration of the ITB. Importantly, the resistance effect plays a dominant role, thus the migration of ITB can be retarded by radiation-induced defects. Furthermore, the underlying mechanism of the double-fold effect was discussed that cross-layer rearrangement of vacancies in the ITB is prevailing in retarded effect on the ITB migration. The present work gives a deeper insight into the effect of radiation-induced defects on the migration of ITB.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114435"},"PeriodicalIF":3.3,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733902","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}
Pub Date : 2025-12-13DOI: 10.1016/j.commatsci.2025.114444
Hongwu Gao , Hangyu Yue , Yinwen Mao , Rengeng Li
Interfaces serve as critical bridges between the matrix and the reinforcement phase, significantly influencing the comprehensive properties of TiAl-based composites. First-principles computational tensile tests combined with crystal orbital Hamilton population (COHP) and electron localization function (ELF) analyses were employed to systematically investigate the evolution of the electronic structure at the Ti2AlC(0001)/TiAl(111) interface during tensile deformation. The strength variations of chemical bonds at the interface—such as TiAl covalent bonds and TiTi metallic bonds—are quantitatively analyzed, and the bond strength is evaluated using the integrated COHP (ICOHP). The results indicated that the critical interfacial fracture strain was 19.5 %, and the theoretical tensile strength was 14.71 GPa. ICOHP analysis revealed that the strengths of the interfacial TiAl and TiTi bonds decreased by 0.471 eV and 0.597 eV at a strain of 18 %, respectively. The -ICOHP values of all interfacial bonds remained positive throughout the deformation process, with the TiAl bond being the strongest (initial -ICOHP = 1.295 eV). This study reveals the fracture mechanism of the Ti2AlC/TiAl interface at the electronic scale, providing theoretical guidance for the design and application of such composites.
{"title":"Revealing the dynamic evolution of the electronic structure at the Ti2AlC/TiAl interface during tensile deformation by the first-principles calculations","authors":"Hongwu Gao , Hangyu Yue , Yinwen Mao , Rengeng Li","doi":"10.1016/j.commatsci.2025.114444","DOIUrl":"10.1016/j.commatsci.2025.114444","url":null,"abstract":"<div><div>Interfaces serve as critical bridges between the matrix and the reinforcement phase, significantly influencing the comprehensive properties of TiAl-based composites. First-principles computational tensile tests combined with crystal orbital Hamilton population (COHP) and electron localization function (ELF) analyses were employed to systematically investigate the evolution of the electronic structure at the Ti<sub>2</sub>AlC(0001)/TiAl(111) interface during tensile deformation. The strength variations of chemical bonds at the interface—such as Ti<img>Al covalent bonds and Ti<img>Ti metallic bonds—are quantitatively analyzed, and the bond strength is evaluated using the integrated COHP (ICOHP). The results indicated that the critical interfacial fracture strain was 19.5 %, and the theoretical tensile strength was 14.71 GPa. ICOHP analysis revealed that the strengths of the interfacial Ti<img>Al and Ti<img>Ti bonds decreased by 0.471 eV and 0.597 eV at a strain of 18 %, respectively. The -ICOHP values of all interfacial bonds remained positive throughout the deformation process, with the Ti<img>Al bond being the strongest (initial -ICOHP = 1.295 eV). This study reveals the fracture mechanism of the Ti<sub>2</sub>AlC/TiAl interface at the electronic scale, providing theoretical guidance for the design and application of such composites.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114444"},"PeriodicalIF":3.3,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734066","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}
Pub Date : 2025-12-13DOI: 10.1016/j.commatsci.2025.114437
Manisha Kumari, Alok Shukla
Potassium sodium niobate (KNN)-based lead-free ceramics are prime prospects for eco-friendly dielectric and piezoelectric technology, and their multi-functionality properties, such as dielectric constant (εr), Curie temperature (Tc), and high piezoelectric coefficient (d33), make them promising materials for next-generation devices. Recent advancements in machine learning (ML) offer the possibility of accelerating materials discovery by prognosticating such properties directly from composition and processing conditions. But current studies are often limited by small datasets, narrow descriptor sets, or a lack of interpretability, leading to models with poor generalization and limited practical utility for guiding experimental synthesis. Therefore, this study developed a single ML framework trained on a large literature-based dataset, utilizing five feature spaces such as compositional, chemical, processing, microstructural, and structural descriptors to estimate d33, εr, and Tc of KNN-based ceramics. Six different ML algorithms were trained and tested for the prediction of each property, and their performance was optimized using a randomized search and a 10-fold cross-validation technique. Among all the developed ML models, the extreme gradient boosting algorithm showed the highest performance with R2 values of 0.93, 0.9781, and 0.9504 for d33, εr, and Tc, respectively, on the test set. For better interpretability of the model, the Shapley Additive Explanation methodology was employed, and it identified and explained the most significant features that contributed to the target performance. Model validity was confirmed by synthesizing compositions withheld from the training data and comparing predictions with the experimental measurements, which exhibited close agreement. This approach offers an interpretable and scalable path to the rapid design of high-performance lead-free dielectric ceramics with verification against data reported in the literature.
{"title":"Machine learning-driven prognostication of multifunctional properties of (K,Na)NbO3-based lead-free ceramics for optimized materials design","authors":"Manisha Kumari, Alok Shukla","doi":"10.1016/j.commatsci.2025.114437","DOIUrl":"10.1016/j.commatsci.2025.114437","url":null,"abstract":"<div><div>Potassium sodium niobate (KNN)-based lead-free ceramics are prime prospects for eco-friendly dielectric and piezoelectric technology, and their multi-functionality properties, such as dielectric constant (<em>ε</em><sub><em>r</em></sub>), Curie temperature (<em>T</em><sub><em>c</em></sub>), and high piezoelectric coefficient (<em>d</em><sub><em>33</em></sub>), make them promising materials for next-generation devices. Recent advancements in machine learning (ML) offer the possibility of accelerating materials discovery by prognosticating such properties directly from composition and processing conditions. But current studies are often limited by small datasets, narrow descriptor sets, or a lack of interpretability, leading to models with poor generalization and limited practical utility for guiding experimental synthesis. Therefore, this study developed a single ML framework trained on a large literature-based dataset, utilizing five feature spaces such as compositional, chemical, processing, microstructural, and structural descriptors to estimate <em>d</em><sub><em>33</em></sub>, <em>ε</em><sub><em>r</em></sub>, and <em>T</em><sub><em>c</em></sub> of KNN-based ceramics. Six different ML algorithms were trained and tested for the prediction of each property, and their performance was optimized using a randomized search and a 10-fold cross-validation technique. Among all the developed ML models, the extreme gradient boosting algorithm showed the highest performance with R<sup>2</sup> values of 0.93, 0.9781, and 0.9504 for <em>d</em><sub><em>33</em></sub>, <em>ε</em><sub><em>r</em></sub>, and <em>T</em><sub><em>c</em></sub>, respectively, on the test set. For better interpretability of the model, the Shapley Additive Explanation methodology was employed, and it identified and explained the most significant features that contributed to the target performance. Model validity was confirmed by synthesizing compositions withheld from the training data and comparing predictions with the experimental measurements, which exhibited close agreement. This approach offers an interpretable and scalable path to the rapid design of high-performance lead-free dielectric ceramics with verification against data reported in the literature.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114437"},"PeriodicalIF":3.3,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145734018","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}
Pub Date : 2025-12-11DOI: 10.1016/j.commatsci.2025.114438
Yashi Jain, Rajnish Kurchania
The rapid emergence of half-metallic materials has spurred accelerated research in materials science, opening the door to novel spintronic applications. The present study systematically explores the structural, magnetic, lattice-dynamical, strain-modulated electronic and transport characteristics of the half-Heusler chalcogenide KVTe using first-principles calculations. The structural, mechanical and thermodynamic stability of the material is analysed through elastic and phonon calculations. The strain-based electronic structure reveals half-metallic ferromagnetic nature of material, with a bandgap of 2.21 eV - 3.53 eV in minority spin state. Electronic properties reveal 100 % spin polarization and a high Curie temperature of 971 K. The figure of merit (zT) is 0.91 and 0.93 for the majority and minority channels, respectively. A high value of zT in both spin states reveals the outstanding thermoelectric efficiency of KVTe. Overall, it finds usefulness in spintronic and thermoelectric devices. It also offers band-gap modulation, suggesting its application in band-gap engineering.
半金属材料的迅速出现加速了材料科学的研究,打开了新型自旋电子应用的大门。本文采用第一性原理计算系统地探讨了半赫斯勒硫化物KVTe的结构、磁性、晶格动力学、应变调制电子和输运特性。通过弹性和声子计算分析了材料的结构、力学和热力学稳定性。基于应变的电子结构显示了材料的半金属铁磁性,在少数自旋状态下带隙为2.21 eV - 3.53 eV。电子特性显示出100%的自旋极化和971 K的高居里温度。多数通道和少数通道的优值(zT)分别为0.91和0.93。两个自旋态的高zT值表明KVTe具有出色的热电效率。总的来说,它在自旋电子和热电器件中很有用。它还提供带隙调制,提示其在带隙工程中的应用。
{"title":"Band gap modulation by strain tuning in half-metallic KVTe","authors":"Yashi Jain, Rajnish Kurchania","doi":"10.1016/j.commatsci.2025.114438","DOIUrl":"10.1016/j.commatsci.2025.114438","url":null,"abstract":"<div><div>The rapid emergence of half-metallic materials has spurred accelerated research in materials science, opening the door to novel spintronic applications. The present study systematically explores the structural, magnetic, lattice-dynamical, strain-modulated electronic and transport characteristics of the half-Heusler chalcogenide KVTe using first-principles calculations. The structural, mechanical and thermodynamic stability of the material is analysed through elastic and phonon calculations. The strain-based electronic structure reveals half-metallic ferromagnetic nature of material, with a bandgap of 2.21 eV - 3.53 eV in minority spin state. Electronic properties reveal 100 % spin polarization and a high Curie temperature of 971 K. The figure of merit (zT) is 0.91 and 0.93 for the majority and minority channels, respectively. A high value of zT in both spin states reveals the outstanding thermoelectric efficiency of KVTe. Overall, it finds usefulness in spintronic and thermoelectric devices. It also offers band-gap modulation, suggesting its application in band-gap engineering.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114438"},"PeriodicalIF":3.3,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733903","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}
Pub Date : 2025-12-10DOI: 10.1016/j.commatsci.2025.114440
Mustafa Erkartal
Exploring how energetic materials respond to compression provides fundamental insight into their stability, reactivity, and design of safer high-performance formulations. This study presents the first investigation of energetic metal-organic frameworks (EMOFs) under hydrostatic pressure. Periodic DFT-D calculations were performed to probe the structural, mechanical, and electronic properties of four 3D EMOFs with experimentally characterized crystal structures. Calculations included full lattice relaxation under pressures of 0–30 GPa, elastic tensor analysis to determine bulk and shear moduli, Hirshfeld surface and two-dimensional fingerprint analyses to examine intermolecular interactions, and electronic structure calculations to obtain pressure-dependent band gaps. Structural and electronic data were then correlated with literature-reported detonation and sensitivity values to elucidate the mechanisms linking lattice motifs, elastic compliance, and electronic stability to energetic behavior. The results reveal that hinge-like deformation, anisotropic elasticity, and pressure-stable band gaps enhance structural resilience, whereas pronounced band gap collapse under compression increases electronic polarizability and sensitivity. These insights provide a foundation for rational design and high-pressure exploration of EMOFs.
{"title":"High-pressure behavior of energetic metal-organic frameworks: A first-principles study","authors":"Mustafa Erkartal","doi":"10.1016/j.commatsci.2025.114440","DOIUrl":"10.1016/j.commatsci.2025.114440","url":null,"abstract":"<div><div>Exploring how energetic materials respond to compression provides fundamental insight into their stability, reactivity, and design of safer high-performance formulations. This study presents the first investigation of energetic metal-organic frameworks (EMOFs) under hydrostatic pressure. Periodic DFT-D calculations were performed to probe the structural, mechanical, and electronic properties of four 3D EMOFs with experimentally characterized crystal structures. Calculations included full lattice relaxation under pressures of 0–30 GPa, elastic tensor analysis to determine bulk and shear moduli, Hirshfeld surface and two-dimensional fingerprint analyses to examine intermolecular interactions, and electronic structure calculations to obtain pressure-dependent band gaps. Structural and electronic data were then correlated with literature-reported detonation and sensitivity values to elucidate the mechanisms linking lattice motifs, elastic compliance, and electronic stability to energetic behavior. The results reveal that hinge-like deformation, anisotropic elasticity, and pressure-stable band gaps enhance structural resilience, whereas pronounced band gap collapse under compression increases electronic polarizability and sensitivity. These insights provide a foundation for rational design and high-pressure exploration of EMOFs.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114440"},"PeriodicalIF":3.3,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733962","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}
Pub Date : 2025-12-10DOI: 10.1016/j.commatsci.2025.114407
Gregor Maier , Jan Hamaekers , Benedikt Ziebarth
Glassy materials are prevalent in many modern-day applications, which place ever new demands on the materials’ properties. However, because of their amorphous nature, the design of glasses with specific properties is inherently difficult and necessarily data-driven. Due to the large size of the compositional space and the cost of the manufacturing process, glass data is only sparsely available. It is thus important to design and train models which maximize the benefit of each individual training sample on the models’ resulting prediction quality. In this paper, we study a multitask learning approach to meet this challenge. We analyze its effect on the sample efficiency, that is, the dependence of the test error on the training set size of a neural network model for predicting properties of oxide glasses. In contrast to existing encoder-based multitask learning models in computational glass science, we propose a decoder-based model, consisting of task embeddings in the input layer and a subsequent shared network architecture. This allows us to apply well-established single-task models in a multitask learning setting. We demonstrate in a series of numerical experiments, predicting the Young’s modulus and the log-viscosity, respectively, that this approach notably improves the model’s sample efficiency. To deal with parametric target properties, we complement the task embeddings by a parameter embedding and show that this preserves the advantageous multitask learning effect. In all experiments, we observe an algebraic scaling law for the decay of the test error with respect to the number of training samples.
{"title":"Multitask learning via task embeddings for glass property prediction with improved sample efficiency","authors":"Gregor Maier , Jan Hamaekers , Benedikt Ziebarth","doi":"10.1016/j.commatsci.2025.114407","DOIUrl":"10.1016/j.commatsci.2025.114407","url":null,"abstract":"<div><div>Glassy materials are prevalent in many modern-day applications, which place ever new demands on the materials’ properties. However, because of their amorphous nature, the design of glasses with specific properties is inherently difficult and necessarily data-driven. Due to the large size of the compositional space and the cost of the manufacturing process, glass data is only sparsely available. It is thus important to design and train models which maximize the benefit of each individual training sample on the models’ resulting prediction quality. In this paper, we study a multitask learning approach to meet this challenge. We analyze its effect on the sample efficiency, that is, the dependence of the test error on the training set size of a neural network model for predicting properties of oxide glasses. In contrast to existing encoder-based multitask learning models in computational glass science, we propose a decoder-based model, consisting of task embeddings in the input layer and a subsequent shared network architecture. This allows us to apply well-established single-task models in a multitask learning setting. We demonstrate in a series of numerical experiments, predicting the Young’s modulus and the log-viscosity, respectively, that this approach notably improves the model’s sample efficiency. To deal with parametric target properties, we complement the task embeddings by a parameter embedding and show that this preserves the advantageous multitask learning effect. In all experiments, we observe an algebraic scaling law for the decay of the test error with respect to the number of training samples.</div></div>","PeriodicalId":10650,"journal":{"name":"Computational Materials Science","volume":"263 ","pages":"Article 114407"},"PeriodicalIF":3.3,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733961","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}