For Pt-based superalloys with a gamma - gamma' dual-phase microstructure, the lattice misfit between the two phases significantly affects the lattice coherent strain field, thereby dictating their mechanical performance. Here, high-throughput first-principles calculations were used to estimate the lattice misfit at finite temperatures. The calculated lattice misfit for Pt3 Al, Pt3 Sc, Pt3 Ti, Pt3 Zr, and Pt3 Hf at 300 K are -0.985%, 0.525%, -0.316%, 1.405% and 0.903%, respectively. Due to the higher antiphase boundary (APB) energy and shear modulus of both Pt3 Al and Pt3 Hf, the combination of Pt3 Hf with positive lattice misfit and Pt3 Al with negative lattice misfit can optimize the overall lattice misfit in Pt3 (Al1-x Hfx )1 through compositional tuning. The calculated lattice misfit for Pt3 (Al0.625 Hf0.375 )1 is -0.154% at 300 K and approaches zero at elevated temperature. The alloy Pt82 Al11.25 Hf6.75 (at.%) was prepared, and in-situ high-temperature X-ray diffraction measurements reveal lattice misfit of -0.135%, -0.20 0%, -0.062%, -0.089%, and 0.060% at 298 K, 573 K, 873 K, 1173 K, and 1473 K, respectively, which agree well with the calculated values. High-resolution transmission electron microscopy (HR-TEM) confirms that the gamma and gamma' phases form a coherent structure. The near-zero lattice misfit induces a coherent strain field around the gamma' precipitates, effectively im peding dislocation motion. The com pressive strengths of Pt82 Al11.25 Hf6.75 at 1173 K and 1473 K were measured as 666.6 MPa and 186.4 MPa, respectively, exceeding those of previously reported Pt-Al-based superalloys. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Single-phase high- and medium-entropy carbides typically require synthesis temperatures above ~2000 °C due to sluggish cation interdiffusion in the carbide lattice. Here, we demonstrate a precursor-engineering strategy using compositionally complex La2Zr2O7-based pyrochlores, in which transition-metal cations are pre-homogenized within a single oxide lattice prior to carbothermal reduction. Single-phase (Zr,Hf,Ta)C is obtained at 1600 °C, while directly mixed oxide systems remain phase-separated under identical conditions due to diffusion-limited interdiffusion among separately formed carbides. DFT calculations confirm that the reaction is thermodynamically favorable and largely composition-insensitive, indicating that single-phase formation is governed by precursor-controlled kinetics rather than thermodynamics. Comparative studies across multiple pyrochlore systems further establish precursor phase purity as the critical requirement, with competing oxide phases reverting the system to conventional diffusion-controlled behavior. These results identify a precursor-controlled pathway for lowering synthesis temperature and improving phase control in compositionally complex carbides.

Uranium monocarbide (UC) exhibits physiochemical characteristics well-suited for nuclear fuel applications in Generation IV reactors, but its high susceptibility to oxidation remains a major barrier to deployment. A detailed understanding of the U-C-O system, including UC thermal oxidation, crystal chemistry, and thermodynamic/kinetic properties, is essential to predict its behavior under normal and off-normal reactor conditions. In this work, in situ high temperature synchrotron X-ray diffraction was conducted under sealed and open-air conditions to characterize UC thermal expansion and oxidation behaviors. From the sealed experiment, the mean coefficient of thermal expansion of UC was determined to be 9.8 × 10−6 K−1 from room temperature to 970 K. Open-air experiments conducted from room temperature to 773 K revealed the oxidation sequence UC → UO2 → U3O8. Notably, a tetragonal U(C1-xOx)2 phase, absent from current thermodynamic predictions, was observed at 840 K, lower than previously considered, suggesting potential relevance for advanced reactor fuel applications. These findings reveal ambiguities in existing knowledge of the U-C-O system, emphasizing the need for continued investigation to facilitate the use of UC-based TRISO and other carbide fuels in emerging reactor designs.

Literature SEM micrographs are a valuable but weakly standardized source for linking γ-TiAl microstructures with tensile properties. Transferable prediction from such data is limited by source leakage, heterogeneous imaging conditions, incomplete processing metadata, and localized strain accumulation during deformation. Here, we develop a provenance-aware, region-resolved framework in which Segment Anything Model 2 (SAM2) is used to generate colony/lamellar, interface-rich, and defect-like region tokens, which are then converted into dimensionless gray-level, texture, orientation, spectral, and edge/defect heterogeneity descriptors. The term "Zentropy-inspired" is used in a restricted sense: the descriptors adopt probability-weighted, multigranular representation logic, but no thermodynamic entropy, free energy, partition function, or temperature-dependent state variable is inferred from SEM contrast. Under paper-level held-out evaluation with near-duplicate suppression, the framework gives R² values of 0.8903/0.9178/0.9359 for elongation/yield strength/ultimate tensile strength in the room-/low-temperature subset (RT/LT, T ≤ 400 °C) and 0.9467/0.8663/0.9516 in the high-temperature subset (HT600, T ≥ 600 °C). Because the HT600 test set contains only 24 held-out records per target, these high-temperature metrics are interpreted as small-sample internal-transfer evidence rather than broad external generalization. Descriptor correlations, residual diagnostics, random-forest (RF) controls, and paper-level error audits indicate that elongation is more sensitive to interface/defect heterogeneity, whereas strength targets are more strongly associated with colony-scale order and pooled heterogeneity. The results support provenance-aware internal transfer within the curated literature dataset and motivate independently curated alloy-family, time-split, or composition-family validation.

Weyl semimetals, characterized by topologically nontrivial band structures, exhibit unconventional transport properties and hold great promise for next-generation electronic devices. When reduced to the nanoscale, the contribution from the topological surface states becomes markedly enhanced, leading to unusual resistivity scaling behaviors. However, the synthesis of nanosized single-crystalline Weyl semimetals remains limited, hindering in-depth investigations of size-dependent transport phenomena. Here, we introduce a novel vapor-liquid-liquid-solid (VLLS) synthesis method for the growth of high-quality single-crystalline NbP nanowires with small diameters and controllable orientations. The VLLS process enables the stable and precise crystallization of NbP guided by Au seeds, favoring growth along the a axis, which has intrinsically lower resistivity. Room-temperature electrical measurements reveal a pronounced decrease in resistivity with decreasing diameter, indicating surface-dominant transport. We achieve a high breakdown current density of 116 MA cm –2 , comparable to that of copper nanowires, and a low resistivity of 21 µΩ cm at ~ 30 nm equivalent diameter, surpassing bulk NbP and many other semimetals. The dominance of topological surface states in charge transport is strongly supported by scanning microwave impedance microscopy measurements and simulations. The VLLS synthesis of NbP nanowires thus not only offers a pathway for precise structural control of Weyl semimetals but also opens new opportunities to tune their transport properties and enable advanced technological applications.

Conventional methods face inherent challenges in simultaneously enhancing the high-temperature strength and microstructural stability of TiAl alloys. To address this limitation, a Ti-48Al-8Nb (at.%) alloy reinforced by in-situ formed micro/nano precipitates was fabricated via directed energy deposition. The introduction of 1.0 at.% Si3N4 promoted the formation of an optimized, uniform equiaxed fully lamellar microstructure interlaced with a multiscale network of Ti5Si3 and Ti2AlN precipitates. The developed metal matrix composite exhibits an ultimate tensile strength of 835 MPa at room temperature-an increase of 153 MPa over the unreinforced additively manufactured Ti-48Al-8Nb baseline alloy (682 MPa). Notably, it demonstrates exceptional strength retention at elevated temperatures, maintaining a UTS of 792 MPa at 850 degrees C, which surpasses that of the unreinforced counterpart (565 MPa) by 227 MPa. Furthermore, the composite displays outstanding microstructural stability, with no evidence of discontinuous coarsening or degradation after prolonged thermal exposure at 1100 degrees C for 200 h. This DED-based strategy, coupled with in-situ precipitation strengthening, establishes a new pathway for developing advanced TiAl composite that combine superior high-temperature performance with long-term microstructural integrity.

Directed energy deposition (DED) is an effective method to process complex components with high efficiency, owing to its significant advantage of material saving and features of microarea metallurgy and rapid solidification. This study presents a nano-Ta-optimized Ti-45Al-8Nb (at%)-based alloy synthesized via DED. The prepared TiAl-based alloy exhibits homogeneously equiaxed grains, compared to the coarse columnar microstructure of pure TiAl alloys without Ta addition. The alloy optimized by Ta exhibits excellent ultimate tensile strength (UTS) at room temperature (950 MPa) and can still maintain a UTS of 751 MPa even at 800 degrees C. Furthermore, the oxidation mass gain of the alloy after 200 h of isothermal oxidation at 850 degrees C is only 0.31 mg cm-2. Especially, the AlTa2 formed during oxidation not only promotes the formation of dense Al2O3 scales but also exhibits a certain coherent relationship with the Al2O3 interface, effectively preventing oxidation and protecting the matrix. The Ta-reinforced alloy helps guide the additive manufacturing (AM) of TiAl-based alloys used at high temperatures (HTs), which feature controllable microstructures and enhanced mechanical properties. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)Ta(sic)(sic)Ti-45Al-8Nb(at%)(sic)(sic)(sic).(sic)(sic)(sic)(sic)Ta(sic)(sic)TiAl(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)TiAl(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)Ta(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(950 MPa),(sic)(sic)(sic)800 degrees C(sic)(sic)(sic)(sic)(sic)751 MPa(sic)(sic)(sic)(sic)(sic).(sic)(sic),(sic)(sic)850 degrees C(sic)(sic)(sic)(sic)200 h(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)0.31 mg cm-2.(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)AlTa2(sic)(sic)(sic)(sic)(sic)(sic)(sic)Al2O3(sic)(sic)(sic)(sic),(sic)(sic)Al2O3(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).Ta(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)TiAl(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

While the recursive property of entropy is well known in information theory, it is rarely utilized in thermodynamics, despite entropy originating in this field. Moreover, computational tools to implement this concept within first-principles thermodynamics remain lacking. In this work, we introduce an open-source Python package, pyzentropy, to implement this approach. We demonstrate its effectiveness using Fe_3Pt as a case study, considering a 12-atom supercell with multiple magnetic configurations. By applying the recursive formulation of entropy to compute the total entropy of the system, we reproduce the Invar behavior, along with the anomalous temperature dependence of the linear coefficient of thermal expansion (LCTE), heat capacity C_P, and bulk modulus B. We also construct the T-V and P-T phase diagrams in good agreement with experimental observations. Finally, we highlight the importance of determining key high-probability configurations to accurately capture material properties.

We recently proposed a unified theoretical framework for superconductivity that broadens the applicability of Bardeen-Cooper-Schrieffer theory to both conventional and unconventional superconductors. Within this framework, superconductivity arises from the formation of a symmetry-broken superconducting configuration (SCC) generated by atomic perturbations of the normal conducting configuration (NCC). The SCC emerges through electron-phonon interactions and gives rise to distinct straight one-dimensional tunnels (SODTs) in the SCC-NCC charge density difference of electrons and/or holes. These SODTs originate from regular and systematic atomic displacements between the SCC and NCC, a phenomenon revealed by density functional theory (DFT) calculations. To further verify this framework, we performed DFT-based calculations for 12 hexagonal close-packed (hcp) elements (Be, Mg, Sc, Y, Ti, Zr, Hf, Tc, Re, Ru, Os, and Zn), 5 body-centered cubic (bcc) elements (V, Nb, Ta, Mo, and W), and the compound Nb3Sn, all examined at 0 K and 0 GPa. Most materials exhibit robust SODTs consistent with known superconducting behavior, while Mg, Sc, and Y are identified as marginal cases, showing functional-dependent SODT signatures indicative of extremely weak superconducting instabilities at ambient pressure. These results support the usefulness of SODTs as a qualitative real-space descriptor of superconductivity-compatible electronic structures within the current limitations of DFT.

In the present work, the density functional theory (DFT) in the generalized-gradient approximation developed by Perdew, Burke, and Ernzerhof (PBE) + U method, i.e., PBE + U, was employed to predict temperature-dependent thermodynamic properties of the rutile-type oxides CrNbO4 and CrTaO4 as well as the binary oxides Cr2O3, Nb2O5, and Ta2O5 via the quasiharmonic phonon approach (QHA). Calculated thermodynamic properties of the binary oxides were benchmarked with experimental data, showing high accuracy except for the negative thermal expansion (NTE) of Nb2O5, attributed to its polymorphic complexity. By combining the formation energy predicted by DFT with the existing SGTE Substances Database (SSUB5), the CrNbO4 and CrTaO4 are found to be thermodynamic stable up to 1706 K and 1926 K and decompose into Cr2O3 and Nb2O5 or Ta2O5 at those temperatures, respectively. The temperature dependence of linear thermal expansion coefficients for CrNbO4 and CrTaO4 are predicted, and their mean values from 500 K to 2000 K are found to be 6.0 x 10-6/K and 5.04 x 10-6/K, respectively, in agreement with experimental observations in the literature. The gas-phase species and their vapor pressure are calculated, indicating that the formation of CrTaO4 and CrNbO4 reduces chromium volatilization, which is critically important to design enhanced refractory high entropy alloys (RHEAs) with enhanced oxidation resistance.

Laser-directed energy deposition (L-DED) enables the fabrication of functionally graded materials (FGMs) with tailored compositions and properties, offering advantages for high-performance applications. In this study, L-DED was adopted to produce FGMs combining stainless steel (SS316L) and nickel-based superalloys (IN625) with graded chemical composition, make it serve as the transition zone in SS316L/IN625 bimetallic structures. The effects of composition gradients under as-deposited (AD) and hot isostatic pressing (HIP) conditions on microstructure and mechanical properties were investigated. A dilution-based model accurately predicted compositional profiles, validated by energy-dispersive X-ray spectroscopy. More Laves phase mixed with carbides were observed in IN625-rich regions (>= 75%) under AD condition with the HIP treatment promoting the dissolution of Laves phase. Meanwhile, the AD FGMs exhibited a transition from weak Goss and Copper textures (25% IN625) to a stronger rotated Cube texture (>= 50% IN625), while HIP led to coarse equiaxed grain formation and texture homogenization. As a result, the local microhardness peaked at similar to 280 HV in 100% IN625 region, while HIP reduced average hardness by 30% across the transition zone and mitigated hardness variation in the initial layers. Micropillar compression tests demonstrated increasing maximum resolved shear stress (MRSS) with IN625 content, with HIP causing 15.8-33.7% reductions from Laves phase dissolution and dislocation density reduction. These results demonstrate the feasibility of L-DED for producing high-performance FGMs and highlight the role of HIP in tailoring microstructure and properties for industrial applications.

Traditional entropy-based methods-such as cross-entropy loss in classification problems-have long been essential tools for representing the information uncertainty and physical disorder in data and for developing artificial intelligence algorithms. However, the rapid growth of data across various domains has introduced new challenges, particularly the integration of heterogeneous datasets with intrinsic disparities. To address this, we introduce a zentropy-enhanced neural network (ZENN), extending zentropy theory into the data science domain via intrinsic entropy, enabling more effective learning from heterogeneous data sources. ZENN simultaneously learns both energy and intrinsic entropy components, capturing the underlying structure of multisource data. To support this, we redesign the neural network architecture to better reflect the intrinsic properties and variability inherent in diverse datasets. We demonstrate the effectiveness of ZENN on classification tasks and energy landscape reconstructions, showing its superior generalization capabilities and robustness-particularly in predicting high-order derivatives. In image and text classification tasks, ZENN demonstrates superior generalization by introducing a learnable temperature variable that models latent multisource heterogeneity, allowing it to surpass stateof-the-art models on CIFAR-10/100, BBC News, and AG News. As a practical application in materials science, we employ ZENN to reconstruct the Helmholtz energy landscape of Fe3Pt using data generated from density functional theory and capture key material behaviors, including negative thermal expansion and the critical point in the temperature-pressure space. Overall, this work presents a zentropy-grounded framework for data-driven machine learning, positioning ZENN as a versatile and robust approach for scientific problems involving complex, heterogeneous datasets.

Tantalum dioxide (TaO2) is a metastable tantalum compound. Here, we report the epitaxial stabilization of TaO2 on Al2O3 (1102) (r-plane sapphire) substrates using suboxide molecular-beam epitaxy and thermal laser epitaxy, demonstrating single-oriented, monodomain growth of anisotropically strained thin films. Microstructural investigation is performed using synchrotron x-ray diffraction and scanning transmission electron microscopy. The tetravalent oxidation state of tantalum is confirmed using x-ray absorption and photoemission spectroscopy as well as electron energy-loss spectroscopy. Optical properties are investigated via spectroscopic ellipsometry and reveal a 0.3 eV Mott gap of the tantalum 5d electrons. Density-functional theory and group theoretical arguments are used to evaluate the limited stability of the rutile phase and reveal the potential to unlock a hidden metal-insulator transition concomitant with a structural phase transition to a distorted rutile phase, akin to NbO2. Our study expands the understanding of tantalum oxides and paves the way for their integration into next-generation electronic and photonic devices.

High-speed laser welding is essential for increasing the production rate of fuel cell fabrication. However, when the welding speed exceeds a critical limit, humping occurs and reduces the weld quality. In this study, two tailored beam configurations, including an adjustable ring mode and a dual-beam configuration, were employed to suppress humping. Computational fluid dynamics simulations were performed to elucidate the underlying suppression mechanisms. The results show that, in the adjustable ring mode, humping mitigation arises from a reduced backward cross-sectional melt flow rate and a more stable molten pool. In the dual-beam configuration, humping suppression is attributed to the deceleration of melt flow, the conduction-mode behavior of the trailing beam, and the widening of the molten pool induced by the trailing laser. Furthermore, because the dual-beam configuration directly modifies the trailing molten pool dynamics, it achieves more effective humping suppression, extending the welding speed limit to 1.50 m/s, compared with 1.00 m/s for the adjustable ring mode. (c) 2026 Published by Elsevier Ltd on behalf of Society of Manufacturing Engineers (SME).

The recursive property of entropy is well known in information theory; however, the concept is underutilized in thermodynamics, despite being the field where the concept of entropy originated. The zentropy approach is built on this idea, and it has emerged as a useful framework for describing thermodynamic systems across multiple scales, yet its statistical-physics foundation has not been fully articulated. In this work, we establish that foundation by showing that the recursive property allows us to coarse-grain thermodynamic systems into the most useful groups, and deriving the Helmholtz energy and partition function by maximizing entropy in its recursive form. This derivation clarifies the thermodynamic meaning of so-called "states that depend on temperature" as coarse-grained configurations, and maintains a clear distinction between the physical and statistical aspects of statistical mechanics. We then illustrate the usefulness of the approach through two representative applications: magnetic materials, where configurations are defined by spin arrangements, and liquids, where configurations are defined by nearest-neighbor environments. In both cases, the framework enables physically meaningful coarse-graining and captures emergent behavior arising from probability redistribution among configurations. These results position zentropy as an exact and flexible multiscale framework for thermodynamics and statistical mechanics, particularly for systems that admit a natural hierarchical grouping of states.

The magnetic ground-state configuration of iron selenide (FeSe) has been a topic of debate, with experimental evidence suggesting the stripe spin fluctuations as predominant at low temperatures, while density functional theory calculations using the exchange-correlation (XC) functional of the generalized gradient approximation (GGA) have historically predicted the antiferromagnetic (AFM) dimer configuration. In this study, we utilize the restored-regularized SCAN (r2SCAN) functional, a variant of the strongly constrained and appropriately normed (SCAN) meta-GGA, to investigate the magnetic configurations of FeSe. It is found that r2SCAN predicts a stripe-AFM ground-state configuration with an antiparallel spin alignment between layers. The energy difference between the parallel and antiparallel interplanar spin alignments is approximately 1.7 meV/atom, predicting a significant but previously unreported interlayer spin coupling not yet observed by experiments. The present study underscores the importance of accurate XC functionals, such as r2SCAN, in predicting the magnetic ground-state configuration of complex materials like FeSe, highlighting its potential to predict magnetic interactions more reliably than traditional GGA functionals by adhering to exact constraints.

Calorimetric determination of enthalpies of mixing (ΔHmix) in multicomponent molten salts is often interpreted using empirical models that lack physically meaningful parameters. However, for improving pyrochemical separation of spent nuclear fuel, where lanthanides are major fission products and critical elements, a deeper thermodynamic understanding of the link between excess thermodynamic properties and solvation structure is critically needed. In this work, we implement a hybrid and physics-informed framework, MIVM+Calorimetry+AIMD, which integrates experimentally measured ΔHmix (via high temperature drop calorimetry) with solvation structures from ab initio molecular dynamics (AIMD). This approach is demonstrated using LaCl3 mixed with eutectic LiCl-KCl (58 mol

We use extensive molecular dynamics simulations to calculate the thermal conductivity and thermal diffusivity in three common molten salts, LiF, LiCl, and KCl. Our analysis includes the total thermal conductivity and intrinsic conductivity, excluding mass currents, measured experimentally. The latter shows good qualitative agreement with the experimental data. We also calculate their key thermodynamic properties, such as constant-pressure and constant-volume specific heats. We subsequently compare the results to the lower bound for thermal diffusivity expressed in terms of fundamental physical constants. Using this comparison and recent theoretical insights into thermodynamic and transport properties in liquids, we interpret thermal properties on the basis of atomistic dynamics and phonon excitations. We finally find that the thermal diffusivity of molten salts is close to their kinematic viscosity.

The Lorenz number (L) contained in the Wiedemann-Franz law represents the ratio of two kinetic parameters of electronic charge carriers: the electronic contribution to the thermal conductivity (Kel) and the electrical conductivity (sigma), and can be expressed as LT = Kel/sigma where T is temperature. We demonstrate that the Lorenz number simply equals to the ratio of two thermodynamic quantities: the electronic heat capacity (cel) and the electrochemical capacitance (cN) through LT = cel/cN, a purely thermodynamic quantity, and thus it can be calculated solely based on the electron density of states of a material. It is shown that our thermodynamic formulation for the Lorenz number leads to: i) the well-known Sommerfeld value L = pi 2/3(kB/e)2 at low temperature limit; ii) the Drude value L = (3/2)(kB/e)2 at the high temperature limit with the free electron gas model, and iii) possible higher values than the Sommerfeld limit for certain semiconductors. Importantly, we demonstrate that the purely electronic contribution to the thermoelectric figure-of-merit can be directly and efficiently computed using high-throughput density functional theory (DFT) calculations, eliminating the need for the computationally intensive Boltzmann transport theory for electronic thermal and electrical conductivities. For thermoelectric materials with low or negligible lattice thermal conductivity, this approach provides a rapid and reliable estimation of the thermoelectric figure-of-merit. These findings highlight the utility of the proposed methodology in high-throughput workflows for thermoelectric material discovery and screening.