Developing metallic materials that simultaneously achieve high strength and ductility remains a critical challenge in advanced engineering applications. Conventional alloys often exhibit a trade-off between these two properties, limiting the design of materials that excel in both. In this study, we propose a novel high entropy alloy design strategy to achieve distinctive high yield strength and excellent ductility through the construction of multiscale heterogeneous structures spanning micrometer to nanometer dimensions. The resulting annealed sample exhibits an exceptional combination of similar to 1.9 GPa yield strength and similar to 10 % fracture elongation, surpassing the mechanical properties of most previously reported HEAs. The outstanding strength primarily stems from precipitation hardening, while deformation is governed by dislocations, stacking faults, Lomer-Cottrell locks, and deformation twins. These microstructural features effectively enhance strain hardening and enable high ductility even at ultrahigh strength levels. Notably, by exploiting the size effect in these multiscale heterogeneous structures, similar to 470 MPa increase in yield strength with only a 3 % reduction in plasticity is achieved. This demonstrates an effective strategy to overcome the traditional strength-ductility trade-off. These insights provide a new pathway for designing precipitation-hardened HEAs with ultrahigh strength and improved ductility. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

The pursuit of high-performance multi-principal element alloys has long been constrained by the strengthductility trade-off. Here, we propose a novel microstructural design strategy that achieves an exceptional balance by architecting a multi-scale, multi-phase heterogeneous microstructure in a CoCrNi-based multi-principal element alloy. This is realized through the synergistic incorporation of three distinct precipitates: coherent L12, incoherent sigma, and Cr-rich body-centered cubic phases. These phases differ markedly in crystal structure, coherency, and chemical composition, enabling concurrent activation of multiple strengthening and deformation mechanisms at different scales, including Orowan strengthening, dislocation slip, heterogeneous deformation induced hardening, Lomer-Cottrell locks, stacking fault networks, and deformation twinning. The designed alloy achieves an excellent combination of mechanical properties with a yield strength of 1216 MPa, an ultimate tensile strength of 1528 MPa, and an elongation of 23 %. This work demonstrates that the deliberate integration of complementary precipitate architectures can effectively break classical mechanical property trade-offs, providing a generalizable microstructural design pathway for designing high-performance advanced structural materials.

The precipitation of topologically close-packed (TCP) phases significantly degrade the creep resistance of superalloys. While prior research predominantly focused on TCP formation under aging conditions, this study is the first to investigate into how creep-induced gamma ' rafting and defects control TCP phase evolution. Compared to aged situations, creep-induced rafting led to delays and a lower volume fraction of mu precipitates, demonstrating for the first time the inhibitory effect of rafting on mu phase formation. Creep-induced gamma ' rafting reduces the gamma ' phase volume fraction, thereby decreasing solute availability in the gamma matrix, which thermodynamically suppresses mu phase precipitation. Simultaneously, dislocation networks forming at gamma/gamma ' interfaces play a dual role. They deplete solute reservoirs to indirectly suppress TCP phases and trap Re element to create localized chemical gradients. These gradients not only promote P phase nucleation but also drive the mu -> P phase transformation. These creep-specific phenomena elucidate novel mechanisms controlling TCP phase evolution and offer pivotal design insights for superalloys subjected to creep dominated service environments.

Ni-based single crystal superalloys for turbine blades experience multimodal creep. Current microstructural design lacks tailored γ-γ′ microstructures for specific conditions. Five initial microstructures with similar morphology and varying γ′ size were creep tested under 980°C/250 MPa and 1100°C/137 MPa. Both conditions showed single-peak creep life evolution, but the creep life peak shifted toward smaller γ′ sizes under the higher temperature. This shift arises from coupled effects of γ′ size on dislocation motion, lattice misfit on interfacial dislocation density and extra damage from TCP phase, offering insights for optimizing microstructures under complex service conditions.

Designing metallic alloys of high strength-ductility synergy has remained an unremitting pursuit for many engineers and scientists. Recent advance in designing multi-principal element alloys (MPEAs) offers an ample and unprecedented space for advanced microstructure design to address this need. In this work, we investigated a strategy to push the strength-ductility trade-off envelop by utilizing multiscale local chemical inhomogeneity created on the principle of negative mixing enthalpy alloying. This is achieved in an FCC CoCrNi MPEA added with Al, Ti and V as negative mixing enthalpy elements to the host elements. This promoted the alloy to form complex structural variations at multiple scales, including short-, medium- and long-range chemical orders; at the nanoscale, L12 nanodomains with varying morphologies and planar fault energies within the FCC matrix; and at the microscale, a bimodal grain size distribution. Such microstructure frustrates and disunifies dislocation resistance, promoting cascading activation of various lattice deformation and hardening mechanisms, such as stacking faults, deformation twins, and L12 nanodomain shearing, during the deformation process. This design yields an exceptional combination of mechanical properties, with a yield strength of ∼1.3 GPa, an ultimate tensile strength of ∼1.92 GPa, and a uniform elongation of ∼28% at ambient temperature. Our findings may provide potential reference for designing various degrees of local chemical ordering in alloys to manipulate the movement of dislocations for achieving high strength and ductility synergy.

This study explores a novel heat treatment process to encourage gamma/gamma(y) interface chemical segregation in a Ni-based single crystal superalloy and investigates the influence of such segregation on the creep life of the alloy. It was found that the specially designed heat treatment process is able to induce Co, Cr and Re segregation at the gamma/gamma(y) interface without affecting the cuboidal morphology of the gamma(y) phase. As a result, the alloy demonstrates much improved creep resistance, with a creep life improvement by 238 % when tested at 760 degrees C/800 MPa. The segregation is also found to reduce dislocation mobility and to slows the gamma(y) phase coarsening rate. With temperature rising, the formation of rafted structures may attenuate these benefits, leading to smaller incremental gains. These findings provide new insights for advancing heat treatment optimization in superalloys.

Precipitation strengthening via coherent L12 nanoprecipitates has emerged as an ideal strategy for designing high-performance materials. Most traditional design methods make it difficult to introduce a pure L12 structure into CoCrNi alloys by adding Al elements, which usually leads to a loss of ductility. This study designed an Al0.3CoCr0.9Ni2.5 multi-principal element alloys through strategic Ni and Al compositional optimization, obtaining a high-density L12 nanoprecipitate structure that exhibits an exceptional combination of high strength and remarkable ductility. The preserved ductility stems from the synergistic interactions between stacking fault networks with Lomer-Cottrell (L-C) locks and deformation twinning. These mechanisms collectively induce a dynamic Hall-Petch effect and shorten the dislocation mean free path, thus enabling the high strain hardening capability. This innovative compositional design strategy demonstrates a viable pathway for designing high-performance precipitation-strengthened alloys.

Interfaces such as grain boundaries, phase interfaces, precipitate/matrix interfaces and defect/matrix interfaces disrupt long-range atomic arrangement order and elemental distribution continuity. Reinforcing interfaces to enhance their mechanical performance and corrosion resistance is essential for their application in harsh service environments. The interfaces of numerous alloys have been mechanically enhanced by processing or element control. In most instances, interfaces still serve as initial oxidation sites, degrading the overall properties of the alloy. Hence, improving the corrosion resistance of an interface is still necessary to improve their applicability. In particular, for Inconel 718 alloys, a primary failure scenario is corrosion-induced failure in harsh working environments, such as high-temperature coupled oxygen-rich environments. This type of failure is normally considered to be initiated from the high quantity of delta/matrix phase interfaces. However, the understanding of the oxidation mechanisms and dynamics initiated at the delta/matrix phase interface is still limited because of a lack of in situ high spatial resolution studies. Here, the thermal oxidation behavior of the semicoherent delta/matrix interface in the Inconel 718 alloy is studied via aberration-corrected environmental transmission electron microscopy (ETEM). The dynamic evolution of the two-phase interface down to the atomic scale is revealed via in situ experiments. Preferential oxidation from the delta/matrix phase interface occurs at relatively low temperatures. Moreover, selective oxidation induces mutual mass transfer on both sides of the interface. Combined with the findings from molecular dynamics simulations, the results confirm that the semicoherent delta/matrix boundary exhibits a large lattice misfit and high energy, which ultimately facilitates the preferential oxidation of the interface. This work provides direct experimental data on the stress corrosion of superalloys and offers reference data for material design and improvement.

The properties of Ga-In-based liquid metal nanoparticles (NPs) are closely related to their microstructure. However, it remains a challenge to realize the controllable gas-phase preparation of such nanoparticles with a wide range of compositions and refined structures. In this study, a synergistic regulation strategy of the source state and deposition pathway during physical vapor deposition was proposed, enabling the preparation of Ga-In NPs over a wide composition range (In content from ∼13 wt% to ∼90 wt%) and with structures ranging from In-rich core-shell particles to homogeneous amorphous particles. The NP structure is strongly correlated with the In content, with a transition region centered near 55 wt% In. A Gibbs free-energy framework calibrated by this experimental critical composition rationalizes the phase-selection behavior: at high In contents, positive mixing enthalpy favours phase separation and core-shell formation, whereas in near-eutectic/Ga-rich compositions, the increasing interfacial-energy penalty inhibits phase separation and promotes homogeneous amorphous structures. This work provides an experimental route and a semi-empirical thermodynamic basis for designing Ga-In nanoparticles with targeted internal structures.

The integration of real-time and flexible imaging has significantly advanced X-ray scintillator imaging technologies. However, combining both functionalities into a single scintillator material remains a fundamental challenge. To address this, we designed a zero-dimensional cerium (III)-based organic-inorganic hybrid halide scintillator, MPH2CeCl5 & centerdot;3H2O (MPH = morpholine), using low-cost solution processing and leveraging Ce (III)'s inherently nanosecond-scale 4f-5d transitions. La3+-alloying induced a dual effect, enhancing the photoluminescence quantum yield to 2.75 times the original value while maintaining a short decay time of approximately 22 ns. Combined with heavy-atom effects, this nanosecond-scale decay prompted investigation of X-ray scintillation performance, revealing a respectable light yield of 10,400 photons/MeV and a low detection limit of 96.73 nGyair/s. By embedding the optimized MPH2CeCl5 & centerdot;3H2O into poly(methyl methacrylate) (PMMA), we fabricated a high-performance flexible film that mitigates material hygroscopicity while enabling outstanding flexibility and dynamic imaging capabilities. This film achieved motion-artifact-free dynamic imaging at 100 fps, clearly resolving blades rotating at 560 degrees/s. This work demonstrates Ce (III)-based halide hybrids as promising platforms for advanced medical and industrial imaging, offering high light yield, rapid response, and superior processability.

The nonoxidative coupling of methane (NOCM) offers a promising route to convert methane into value-added chemicals. Liquid metals have emerged as potential catalysts for NOCM, due to their propensity against coke formation and the flexible atomic arrangement that facilitates methane activation, with liquid state indium (In) gaining attention. However, the reaction pathways and catalytic mechanisms of In during NOCM have yet to be fully understood. Here, we report the discovery of locally generated In liquid metal active sites on In2O3 for the NOCM reaction, supported by silicon dioxide substrates, in the vicinity of an in situ formed In silicon oxide (In2Si2O7) interfacial layer. By the implementation of combined in situ transmission electron microscopy and electron energy loss spectroscopy, we directly observed the formation of liquid metal "In active sites", near the interfacial layer, at >600 °C. The spectroscopy analysis reveals that In2Si2O7 is a reservoir in methane conversion, storing reactive H* and CH x * intermediate spillover from "In" for driving the NOCM reaction, avoiding the overcracking of CH4 over metallic In. This finding provides a practical approach for the rational design of efficient and noncorrosive liquid metal-based catalysts.

Intermetallic alloys, recognized for the long-range atomic ordering and resultant impressive mechanical properties, are highly sought after in various advanced fields, including aerospace, automotive, and nuclear energy. However, their widespread application is still hindered seriously due to the poor fatigue endurance. Here, we design a new-type L12-structured multi-element symbiotic intermetallic alloy (MSIMA) and achieve a fatigue limit of ~1,100 MPa that remarkably surpasses its yield strength by 1.1 times, which is superior to other structural alloys currently in use. The complex sublattice occupation strengthens the alloy by increasing the antiphase boundary energy of the superlattice, thereby suppressing the fatigue-induced lattice defects. Concurrently, the multi-element symbiosis enables the modulation of local chemistries and the architecting of the disordered interfacial nanolayer (DINL) near grain boundaries, thereby shifting the fatigue fracture mode from intergranular to transgranular cracking. Furthermore, serving as the ductilizing sources, these DINLs facilitate the unusual anti-fatigue mechanisms-mechanical faulting and twinning-that are rarely observed in ordered alloys at room temperature. This deformation behavior effectively alleviates the strain localization and blunts the crack propagation, thereby enhancing their fatigue resistance.

Proton exchange membrane (PEM) fuel cells and water electrolyzers require systematic water management for robust operation. However, current water management strategies only focus on single-side electrode and usual condition, lacking device-level overall and multi-status adaptive considerations. Herein, a nanocomposite PEM-presided strategy realizes holistic and flexible water management. Lamellar hydrophilic talcum is modified to produce magnetic-responsive nano-fillers, which are composited with Nafion matrix under magnetic field to construct PEMs with well-spread straight-forward water diffusion pathways along the membrane through-plane (TP) direction. This strategy accommodates rapid non-tortuous TP water transport in PEM, realizing overall water balance within holistic membrane electrode assembly under various conditions. Applied in devices, the TP-oriented nanocomposite PEM enables self-regulated well-deployed water management, which markedly promotes the electrochemical processes related to water/gas distribution and transfer, achieving 2026mWcm-2 or 2.75Acm-2 at 2V for PEM fuel cell or water electrolyzer with little performance decay after 500h harsh and variable operation. This nanocomposite PEM-presided holistic and flexible strategy offers shifting insight and efficacy for water management of fuel cells and water electrolyzers.

Cu/ZnO/ZrO2 (CZZ) catalysts are widely used in CO2 hydrogenation to methanol. However, their structural dynamics under reaction conditions and related reaction mechanism remain unclear. In this study, we employed in-situ transmission electron microscopy (TEM) to investigate structural changes in Cu/ZnO/ZrO2 catalysts under CO2 and H2/CO2 environments at 200 degrees C and 250 degrees C. Under CO2 conditions, coexisting CuO and ZnO phases were observed along with a diminishing crystalline ZrO2 phase. Under H2/CO2 conditions, dynamic formation and evolution of a CuZn alloy phase occurred, accompanied by the reappearance of crystalline ZrO2 nano-particles. It is also noted that copper in Cu/ZnO/ZrO2 is difficult to be completely reduced in a H2/CO2 environment, in contrast to un-supported CuO nanoparticles. These results suggest a distinct function of ZrO2 and ZnO support in the catalyst, which alters the catalytic performance of the CZZ system. The findings of this study provide new insight into the dynamic behavior of CZZ catalysts under actual reaction conditions.

Advanced alloys that maintain both high strength and ductility at different service temperatures are crucial for demanding applications in extreme environments. However, achieving high strength and ductility simultaneously at different temperatures remains challenging due to the occurrence of the ductile-brittle transition. In this study, we report a novel (FeCoNiV)93Al5Ti2 high-entropy alloy with a hierarchical multi-component heterogeneous microstructure that achieves an exceptional strength-ductility synergy at both 298 and 77 K. Through valence electron concentrations-guided compositional design and optimized thermo-mechanical processing, a complex microstructure comprising an L12-B2 dual-phase matrix with reciprocal precipitation and spinodal decomposed B2(1)/B2(2) nanodomains is designed. The alloy exhibits an ultimate tensile strength of similar to 1841 MPa with a tensile elongation of similar to 23% at 298 K and an ultimate tensile strength of similar to 2285 MPa with a tensile elongation of similar to 20% at 77 K. These remarkable mechanical properties are attributed to the synergistic activation of the multiple strengthening and deformation mechanisms, including hetero-deformation induced hardening, Orowan-bypass mechanism, stacking faults, Lomer-Cottrell locks, nanotwins, and spinodal hardening. (c) 2026 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Understanding the plastic behavior at crack tips is critical for enhancing the fracture toughness of nanometals. Although extensive research has been conducted, most previous studies have focused on pure metals, and how the crack tips accommodate plastic deformation in highly concentrated solid-solution alloys remain unclear due to limited atomic-scale evidence. In this study, the atomic-scale plastic behavior of crack tips in face-centered cubic (FCC) AuCu nanocrystals is investigated in situ. The results provide direct evidence that plastic deformation is governed by sequential activation of different deformation mechanisms, i.e., full dislocation activities first, then followed by random twinning/detwinning, and finally dislocation-twin interactions, which are rarely observed in pure metals. These deformation processes collectively enhance the fracture toughness of the nanocrystals, representing a previously unrecognized mechanism for fracture toughness improvement in metals. This work not only offers atomic-scale insights into the deformation behavior of nano-alloy materials but also provides new perspectives for the design of high-performance alloys with superior fracture resistance.

Two-dimensional tungsten disulfide (2D WS2) has attracted significant attention across diverse application fields, particularly optoelectronic devices and field-effect transistors, due to its exceptional properties. A thorough elucidation of the WS2 growth mechanism is crucial for device implementation, as it allows for precise modulation of the nanoscale properties. Despite significant efforts toward the growth of 2D WS2 for increasing its size, detailed investigations into its structural evolution, especially for the out-of-plane layered WS2, remain scarce. In this work, we identify two distinct conversion growth mechanisms for in-plane and out-of-plane layered WS2 using a homemade chemical vapor deposition (CVD) system. We systematically investigate the evolution of different WS2 nanophases by altering the precursor and regulating the sulphur concentrations. The results reveal that out-of-plane 1D and 2D WS2 are formed via an outside-in mechanism during the layer-by-layer sulphurization of WO2.7 nanowires, while in-plane layered WS2 evolves from WO3 precursors via a 'self-seeding' mechanism involving an island-like WO3-x-WS2 core-shell structure. This study clarifies the 2D WS2 growth process, offering key insights into the evolution mechanisms of low-dimensional WS2. These findings may not only pave the way for synthesizing high-quality, large-scale 2D-domain WS2 but also offer guidance for the controlled growth of other transition-metal dichalcogenides.

Inorganic all-solid-state electrochromic devices (ECDs) are promising for smart windows and adaptive optoelectronics, but they often suffer from insufficient optical contrast, slow switching kinetics and poor cycling stability. High-voltage operation enhances optical modulation and redox kinetics, yet it accelerates metastable phase transitions and structural degradation. Here, we reveal that the degradation of NiO-based ECDs under high-voltage cycling originates from strengthened Ni-O covalency and the accumulation of metastable H1-3 phases, during the O3-O1 transition, which suppresses Ni regeneration and stress-buffering heterojunctions formation. To address this, we propose a covalency modulation strategy via Mo6+ doping. In-situ characterizations and theoretical calculations reveal that Mo incorporation weakens Ni-O bonding, enabling the in-situ formation of regenerable Ni/MoxNi1-xOy heterojunctions. The resulting ECD achieves exceptional durability over 17,000 cycles without performance degradation, together with high optical modulation (82.09%) and superior coloration efficiency (236.51 cm2 C-1), providing a general strategy toward durable high-voltage electrochromic and energy devices.

Refractory multi-principal element alloys (RMPEAs) are promising structural materials for aerospace and nuclear applications due to their exceptional mechanical properties. However, these alloys face two critical challenges: intrinsic room-temperature brittleness caused by restricted dislocation mobility and limited strain hardening capacity resulting from planar slip-dominated deformation. This study proposes a novel thermomechanical processing route termed CRLAPA (cold rolling followed by low-temperature aging and partial annealing) to construct multiscale heterostructures in a Ti33Zr33Nb20Al9V5 RMPEA, thereby achieving a high tensile yield strength of 1323 MPa with 19% fracture elongation. The bimodal grain structure, engineered via recrystallization driven by dislocation density gradients, facilitates complementary deformation modes: ultrafine grains effectively store geometrically necessary dislocations (GNDs) for rapid hardening, whereas fine grains accommodate statistically stored dislocations (SSDs) to sustain plastic flow. The B2-type short-range order (SRO) in conjunction with enhanced local lattice distortion, promotes the formation of slip bands by effectively pinning dislocation motion and thereby facilitating dislocation multiplication. These slip bands interact with microbands to form stress redistribution pathways, thereby delaying strain localization and maintaining sustained work hardening. This work establishes a viable strategy for overcoming the strength-ductility trade-off in RMPEAs by multimodal regulation of multiscale barriers.

Hot cracking remains a critical challenge limiting the widespread adoption of superalloys in additive manufacturing. This defect primarily originates from stress-induced rupture of intergranular residual liquid films that persist during final solidification, typically comprising low-melting-point phases formed through solute-segregation. This understanding has guided conventional crack suppression strategies focused on eliminating such residual phases by strict compositional controls. Herein, an innovative approach is demonstrated that strategically engineers residual eutectic fractions (>= 2 vol.%) through trace element regulation to achieve an intrinsic capability for crack suppression. Hastelloy X is selected as the model system owing to its marked hot cracking susceptibility. Leveraging the ultra-low partition coefficient (k = 0.21) of carbon, a subtle increment in its content (<0.1 wt.%) significantly enhances the formation of ternary eutectic carbides through amplified segregation. The resulting adequate eutectic liquids successfully prevent crack initiation through stress-compensating backfilling while preserving structural cohesion via liquid buffering, revealing the context-dependent duality of eutectics-transitioning from crack initiators to healers. These crack-free samples exhibit superior strength-ductility synergy compared to carbon-restricted counterparts, benefiting from combined effects of carbide dispersion strengthening and multiple dynamic hardening mechanisms.