With the trend towards material integration, the mechanical properties of phase boundary (i.e., interface) are crucial for robustness in industrial applications. Especially in age-hardenable alloy-based composites, the understanding on interfacial mechanical properties with varying aging conditions remains elusive. Here we utilized an engineering SiC/Al-Zn-Mg-Cu (7A04) alloy composite as a model system, to uncover the impact of agingmediated precipitate evolution and elemental redistribution on the interfacial properties. Small angle neutron scattering (SANS), complemented by transmission electron microscopy (TEM), was employed to quantify the nature of the precipitates within bulk specimens. In situ micro-compression tests were performed to precisely determine their corresponding interfacial strength and energy density. Per kinetic and thermodynamic analysis, the most compelling synergy of interfacial strength (similar to 284 MPa) and energy density (similar to 18 MJ center dot m(-3)) in the peakaged composite arises from the tailored precipitation hardening in the matrix, improved interfacial wettability by Mg segregation, and an optimally balanced interfacial zone that delays failure. These findings not only reveal the quantitative correlation between interfacial microstructures and properties, but also pave the way for tunable interfaces that confer high-performance in structural materials.

Long-term stability of neural interfaces is frequently compromised by mechanical mismatch and chronic neuroinflammation, often leading to electrode detachment and signal failure. While hydrogel coatings offer a solution, conventional designs typically rely on exogenous conductive fillers that can sacrifice mechanical flexibility or induce toxicity. Here, we report on a soft neural interface based on the supramolecular co-assembly of a renewable natural polysaccharide, okra mucilage polysaccharide (OMP), and an α-helical peptide amphiphiles (APA). The resulting OMP-APA hydrogel (OP gel) exhibits environment-responsive enhancements in bioadhesion and charge-transport capability triggered by physiological pH and electrical stimulation. These properties arise from intrinsic, stimulus-responsive alterations in fibre architecture and orientation, eliminating the need for conductive fillers. Leveraging interfacial liquid-liquid phase separation, we demonstrate the in situ coating of ultra-thin OP-gel coating onto carbon fibre electrodes (CFE). The OP-gel-coated electrodes (OP-CFE) significantly mitigate foreign body responses and glial scarring, enabling stable, high-quality neural recordings in a mouse cortical in vivo model. Our findings provide a versatile strategy for constructing seamless, multifunctional bio-interfaces through supramolecular co-assembly, with broad implications for advancing neural prosthetics and neuroscience research.

Al-Zn-Mg-Cu alloys are a class of high-strength aluminum alloys widely used in the aerospace and transportation industries. However, these alloys are susceptible to grain coarsening and elemental segregation during solidification. Hence, the solidification behavior, aging precipitation, and mechanical properties of Al-Zn-Mg-Cu alloy with Sc and Zr addition were systematically studied by X-ray diffraction, differential scanning calorimetry (DSC), in-situ synchrotron X-ray radiography, small-angle neutron scattering (SANS), scanning/transmission electron microscopy (SEM/TEM), and nanoindentation test. The results show that Sc/Zr addition is associated with pronounced refinement of the primary α-Al dendrites, particularly at low cooling rates. During aging, the Sc/Zr-containing alloy exhibits improved long-term precipitate stability, with the average precipitate size reaching approximately 7.1 nm after aging at 160 °C for 24 h, compared with 10.3 nm in the base alloy. Quantitative TEM analysis further shows that the Al₃(Sc,Zr) dispersoids maintain an average diameter of approximately 24–27 nm over the investigated aging conditions, demonstrating their high dimensional stability. At 160 °C, the Sc/Zr-containing alloy exhibits improved hardness retention during prolonged aging; after 24 h, its Vickers hardness remains 168.2 HV compared with 140.1 HV for the base alloy. These results indicate that Sc/Zr microalloying primarily helps improve the long-term microstructure and mechanical stability of Al-Zn-Mg-Cu alloys, rather than fundamentally altering their precipitation sequence, providing a theoretical framework for designing novel alloys that combine ultra-high strength and excellent anti-coarsening properties.

The structural nature of amorphous materials remains a long-standing challenge in condensed matter physics. The emergence of order within disorder has driven significant breakthroughs, including the discovery of quasicrystals and structural motifs in amorphous systems. Among these motifs, ring structures, which exhibit rotational symmetry without translational symmetry, play a crucial role in enabling fractal packing and longrange disorder in network glasses, such as oxide, chalcogenide, and halide systems. However, their universality in simple atomic systems, like metallic glasses, remains unsolved. Here, a four-membered Frank-Kasper (FK) cluster ring structure, denoted as 4M-Ring, has been proposed to be a consistent structural model for a metastable amorphous phase of Cu-Zr-Al-Y bulk metallic glasses. This medium-range structural motif, about 15 & Aring;, is geometrically stable and energetically favorable. The addition of yttrium (Y) as a minor alloying element facilitates the formation of the 4M-Ring by occupying its central position and linking four edge-sharing FK polyhedra. Furthermore, evidence from electron microscopy and small-angle neutron scattering suggests that 4MRings organize into a nanoscale network with diffuse interfaces, reducing interfacial energy and enhancing exceptional thermal stability. Our findings suggest the possibility of the presence of novel Frank-Kasper mediumrange order in metallic glasses with minor additions and reveal new structural principles that govern amorphous materials.

Fabricating high-performance multi-principal element alloys (MPEAs) via binder jet 3D printing (BJ3DP) including binder jetting and sintering two main processes, remains a considerable challenge due to low relativedensity and limited strengthening mechanisms. In this work, L12 precipitates and supersolidus liquid-phase sintering (SLPS) were synergistically utilized to solve this dilemma in a BJ3DP fabricated MPEA based on NiCoCr matrix. Following SLPS, the BJ3DP alloy exhibits near-full relative density (-99.3 %), showing an isotropic-microstructure without residual-stress, and comprises a face-centered cubic (FCC) matrix containing high-density L12 precipitates (- 137 nm) and sparse smaller ones (-12 nm). The high relative-density and dualscale precipitations synergistically lead to the exceptional mechanical performance at room-temperature, displaying a yield strength of -915 MPa, an ultimate tensile strength of -1130 MPa and an elongation of -7 %. Orowan mechanism was identified as the primary strengthening mechanism. These findings demonstrate a viable pathway for fabricating high-performance MPEAs via BJ3DP.

Strengthening of Invar alloys is often accompanied by compromising their low coefficient of thermal expansion (CTE), which has been restricting the development of high-strength yet low CTE Invar alloys. Herein, by leveraging the opposite effect of Co and V on CTE, we designed a novel high-strength and low CTE Invar alloy. Laser powder bed fusion (LPBF) technique was used to fabricate the material. Results showed that this novel Invar alloy demonstrates excellent printability, which can achieve near-full density ( > 99.5 %) in a wide processing window. An optimal direct aging treatment process of 3 h at 650 degrees C was determined to maximize its strength. TEM and in situ small-angle neutron scattering (SANS) analysis showed that VC nanoparticles as fine as 10 nm precipitate upon heat treatment. Tensile tests revealed that the peak-aged specimen possesses a high yield strength of 600 MPa, reflecting about 50 % enhancement compared with LPBF-processed conventional Invar alloys. Such a strength increase is primarily contributed by Orowan strengthening of those ultra-fine VC nanoparticles. Meanwhile, a relatively low CTE (1.41 x 10-6 degrees C-1 , 30-150 degrees C) has been maintained. The combination of high strength and low CTE of this novel Invar alloy is superior to that of additively manufactured Invar in the literature. This work offers a pathway to increase the strength of Invar alloys without sacrificing their low CTE. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

The widely used marine materials, nickel aluminum bronzes (NAB), are facing a bottleneck of improving their limited strength and moderate corrosion resistance. In this study, we proposed a novel face-centered cubic (FCC) Cu48Ni17Cr10Al10Co7Fe5Mn3 (at.%) medium-entropy alloy (MEA) strengthened by coherent L1(2) nanoprecipitates and two types of other secondary phases. One secondary phase exhibited FCC/L1(2) structure with spinodal decomposition, while the other BCC/B2 phase displayed a core-shell structure. Compared with the typical as-cast NAB, the mechanical properties and corrosion resistance of the as-cast Cu-rich MEA were simultaneously improved. Specifically, its tensile yield strength was increased from similar to 343 MPa to similar to 564 MPa, total elongation was increased from similar to 22.4 % to similar to 26.5 %, and corrosion current density was reduced by three orders of magnitude. Our results confirmed that the Cu-rich MEA displays a heretofore unattainable combination of mechanical performance and corrosion resistance when compared to those of previously studied Cu-bearing alloys. This impressive combination of strength and ductility was primarily attributed to the synergistic effect of multiple secondary phases, and outstanding corrosion resistance originated from the stabilized and dense passive film. The results presented here validate the hypothesis that the concept of Cu-rich MEA provides a powerful strategy to enhance the corrosion resistance and mechanical response of conventional Cu-bearing alloys.

Understanding the solution-state aggregation of conjugated polymers is essential for controlling their film microstructure and improving optoelectronic device performance. However, resolving aggregate structures in donor:acceptor blends remains challenging due to limited contrast and the multicomponent nature of these systems. Here, we selectively deuterate the side chains of poly(3-hexylthiophene) (P3HT) to produce P3HT-D, substantially increasing its neutron scattering length density (SLD). This isotopic modification enables high-contrast small-angle neutron scattering (SANS) analysis of polymer aggregation in solutions of polymer:nonfullerene acceptor (NFA) blends. The enhanced contrast overcomes the deficiencies of conventional X-ray scattering and microscopy, allowing for unambiguous determination of chain conformation and aggregate structure. Photodiodes incorporating P3HT-D show improved responsivity and achieve a high specific detectivity of 5.67 x 1013 Jones. These improvements are attributed to refined film morphology, improved miscibility, and reduced nonradiative recombination facilitated by isotopic substitution. Our findings demonstrate that side-chain deuteration provides a dual benefit: (i) enabling precise structural characterization and (ii) tuning intermolecular interactions to improve device performance. This study establishes side-chain deuteration as a versatile strategy for structural analysis, microstructure engineering, and performance optimization in conjugated polymer-based organic photodiodes.

Nanoparticles offer strong potential as water-based lubricant additives, but their tendency to aggregate in aqueous media leads to poor dispersion and unstable tribofilms, limiting tribological enhancement. We developed a hybrid core-shell system composed of poly(acrylic acid)-modified Fe3O4 (Fe3O4@PAA) and aminofunctionalized SiO2 (SiO2-NH2). Small-angle neutron scattering (SANS) and dynamic light scattering (DLS) was used to analyze the colloidal stability and concentration-dependent aggregation of Fe3O4@PAA, while tribological testing revealed how surface chemistry governs tribofilm formation and lubrication performance. Results show that Fe3O4@PAA maintains a stable core-shell structure with good dispersibility influenced by concentration. During friction, multipoint binding of PAA chains forms a polycarboxylate network, and incorporation of SiO2-NH2 reinforces this network and enhances tribofilm stability. At a load of 100 N, the optimum mixture (1 wt% Fe3O4@PAA and 1.2 wt% SiO2-NH2) reduced the friction coefficient (COF) and wear volume by 74.8 % and 67.8 %, respectively. The proposed "polycarboxylate interfacial network" strategy overcomes the limitations of single-particle systems under high load, highlighting a new pathway for designing efficient, ecofriendly water-based lubricants.

This study systematically investigates the effects of AlCu addition on the microstructural evolution and mechanical properties of (FeCoCrNi)(100-x)(AlCu)(x) (x = 0, 5, 10, 15, 20; at%) high-entropy alloys (HEAs). The results reveal that the microstructure evolves from coarse equiaxed to refined equiaxed, dendritic, and ultimately dual-phase morphology with increasing AlCu content. Furthermore, the nanoscale structure evolution was investigated by the small-angle neutron scattering (SANS) technique. The results show that with 10 at% AlCu addition, spinodal decomposition (with a wavelength of lambda(SD) = 1.3 nm) occurred in the FCC matrix. This structure evolved into L1(2)-ordered precipitates (with a radius of 2.15 nm and a volume fraction of 14.68%) within the dendrites, accompanied by interdendritic FeCr-rich BCC and Cu-rich B2 phases, upon increasing the AlCu content to 15 at%. It is found that the addition of AlCu induces the internal friction (IF) peaks shift to lower temperatures with enhanced intensity, exhibiting maximum activation energy at 15 at%, coinciding with BCC precipitation. The microstructure alteration leads to a monotonic increase in the microhardness. Although higher AlCu content can improve yield/tensile strength, it reduces ductility. Notably, the (AlCu)15 HEA achieves an exceptional strength-ductility balance, primarily attributable to the L1(2) precipitation strengthening. This study indicates the critical role of AlCu addition in overcoming the strength-ductility trade-off of HEAs.

Al-Zn-Mg-Cu alloy is a kind of high-strength alloys and widely used in the aerospace and transport industry. While, the coarse grains and segregation behavior usually occurred in the studied alloys. Hence, the solidification behavior, aging precipitation, and mechanical properties of Al-Zn-Mg-Cu alloy with Sc and Zr addition were systematically studied by X-ray diffraction, differential scanning calorimetry (DSC), in-situ synchrotron X-ray radiography, small-angle neutron scattering (SANS), scanning/transmission electron microscopy (SEM/TEM), and nanoindentation test. The introduction of Sc and Zr promotes the formation of Al3(Sc, Zr) particles and then enhance the heterogeneous nucleation of primary Al by inducing intense constitutional supercooling. This significantly refines the α-Al dendrites from a coarse dendritic morphology into fine, dispersed equiaxed grains. The highly coherent Al3(Sc,Zr) precipitates substantially accelerate the nucleation of the η′ precipitate phase during the early stages of aging. Furthermore, under long-time, high-temperature aging at 160°C, the strongly suppress the Ostwald ripening of the η′ phase through their robust spatial pinning and vacancy trapping effects. Quantitative analyses via SANS and TEM demonstrate that after aging at 160°C for 24h, the radius of the precipitates in the modified alloy reaches approximately 3.55 nm, whereas the base alloy undergoes severe coarsening (about 5.25 nm). At 160 ℃, the Sc-Zr modified alloy exhibits superior thermal stability (Hardness: 168.2 HV, Elastic modulus: 81 GPa), effectively mitigating the coarsening-induced softening observed in the base alloy (140.1 HV, 73.6 GPa). This work demonstrates that Sc/Zr microalloying yields a thermally stable, dual-level nanoscale strengthening system, offering a theoretical framework for designing novel alloys combining ultra-high strength with exceptional coarsening resistance.

PEGylated liposomes are widely used as drug delivery carriers due to their prolonged circulation and enhanced accumulation at pathological sites. However, repeated administration can trigger the accelerated blood clearance (ABC) phenomenon, reducing delivery efficacy. Herein, we report a zwitterionic PEGylation strategy by grafting glutamic acid-lysine (EK) peptides onto PEGylated phospholipid derivatives to assemble liposome (Lip)-based drug delivery systems. Small-angle neutron scattering analysis confirmed that EK modification significantly enhanced Lip hydration, leading to a 40-fold reduction in protein adsorption compared to conventional PEGylation, which therefore reduced immune cell uptake, anti-PEG antibody production, and nonspecific hepatic accumulation of EK-Lip. Furthermore, even in the presence of preexisting APAs, EK-Lip could mitigate the ABC effect and exhibit a twofold increase in the area under the curve of the pharmacokinetic profile after multiple injections compared to Lip. When loaded with doxorubicin, the zwitterionic EK-Lip demonstrated lower immunogenicity and superior antitumor efficacy compared to conventional formulations. This work provides a facile strategy to assemble zwitterionic liposomes with modified surface chemistry, offering a promising solution to the ABC effect in PEGylated liposomes.

Water-based lubrication systems are increasingly attractive due to their environmental friendliness, costeffectiveness, and safety merits. While oleic acid-modified magnetite nanoparticles (Fe3O4-OA) have demonstrated promising properties as lubricant additives in oil-based systems, their performance in water-based lubrication systems remains largely unexplored, as the Fe3O4-OA nanoparticles exhibit limited dispersion stability and tribological performance in aqueous environments. In this study, Fe3O4-OA was combined with aminefunctionalized silica (SiO2-NH2) nanoparticles to enhance the anti-friction and anti-wear properties in water-based lubrication. Comparative tribological tests showed that adding 1 wt% Fe3O4-OA and 1 wt% SiO2-NH2 reduced the coefficient of friction by 72.4% and the wear volume by 81.7% under a 100 N load compared with pure water. Small-angle neutron scattering (SANS) analysis reveals that increasing Fe3O4-OA concentration led to a more extended configuration of oleic acid molecular chains, facilitating interactions with surface amine groups on SiO2-NH2. These interactions promote the formation of a stable and compact tribofilm through combined Lewis acid-base coordination, hydrogen bonding, and electrostatic attraction. The improved frictional performance provides insights into the rational design of high-performance, water-based lubrication systems via nanoparticle additives.

Small angle neutron scattering (SANS) is a bulk-sensitive technique for characterizing structural heterogeneity over nanometer-to-mesoscopic length scales. Its sensitivity to nuclear scattering length density contrast, isotopic substitution, neutron penetration, and magnetic scattering makes SANS particularly useful for probing bulk nanoscale structures, light-element distributions, and magnetic correlations that are difficult to access using conventional X-ray- or electron-based methods. This review summarizes the fundamentals, instrumentation, methodological advances, data analysis, and representative applications of SANS. Particular attention is given to neutron sources, spectrometer performance, in-situ sample environments, grazing incidence SANS, contrast variation, and model-based interpretation. Representative applications in metallic alloys, polymers, and biological systems are discussed to illustrate the scope, analytical capabilities, and future potential of SANS in the study of complex mesoscale structures. Future opportunities are considered in terms of contrast design, time-resolved and in-situ measurements, reliable data analysis, and integration with data-driven approaches.

It is well-known that the formation of Mn-Ni-Si precipitates in reactor pressure vessel (RPV) steels during extended service in nuclear power plants results in hardening and embrittlement. However, the migration and local aggregation behavior of solute atoms in the early service period remains elusive due to limitations in characterization techniques. In this work, the migration and aggregation behavior of solute atoms, along with the thermodynamic characteristics of C-bearing Mn-Si-rich phases (C-MSPs) precipitated along grain boundaries (GBs) during the early aging period of RPV steels were systematically investigated using internal friction (IF), transmission electron microscopy (TEM), and small-angle scattering (SAS) techniques. The IF results reveal three primary peaks, designated as P-1, P-2, and P-3, where the P-1 and P-2 correspond to C-Snoek peaks influenced by Mn, Ni, and Si atoms, while the P-3 represents GB relaxation modulated by the content of C-MSPs precipitated at GBs. During short-term aging (<= 5 h), the height of the P-1 decreases consistently, whereas the P-2 initially increases and then decreases, indicating that C atoms initially interact with substituent atoms (Me=Mn, Ni, and Si) to form C-Me pairs and subsequently co-precipitate as C-MSPs at GBs, with solute atoms aggregation and precipitation occurring concurrently over an extended period (<= 100 h). The height of the P-3 decreases with increasing aging time and temperature, reflecting a gradual increase in C-MSPs content at GBs, consistent with TEM and SAS observations. Activation energies of 0.87 and 1.30 eV for solute aggregation and precipitation of C-MSPs, respectively, suggest that the growth of C-MSPs is predominantly governed by GB diffusion. Furthermore, a schematic diagram illustrating solute atom migration, C-MSPs nucleation, and growth, along with a time-temperature-transformation (TTT) diagram for C-MSPs evolution is provided. This work portrays the landscape map of the microstructural evolution of RPV steels during the early service period, offering valuable insights for guiding the compositional design of RPV steels. (c) 2025 Published by Elsevier Ltd on behalf of Theeditorial office of Journal of Materials Science & Technology.

Ostwald ripening is ubiquitous in colloidal growth yet is rarely recognized as a dominant pathway in polymer self-assembly. Herein, we investigate the solution self-assembly of liquid-crystalline polypeptoids based on poly(N-2-ethyl-1-hexyl glycine) (PNEHG) homopolymers and their amphiphilic block copolymers. Upon supersaturation, PNEHG homopolymers form micrometer-sized, highly symmetric hexagonal platelets primarily through Ostwald ripening. This behavior arises from rod-like PNEHG chains packing into a columnar hexagonal (Colhex) mesophase with long-range orientational order and short-range positional order, enabling continuous structural rearrangement during growth. Incorporation of a solvophilic poly(N-methyl glycine) (PNMG) block induces a morphological transition from flat platelets to hexagonal spirals with periodic screw dislocations and continuous helical ramps, which is driven by steric constraints at the core-corona interface that introduce packing frustration and redirect mesogenic growth. These findings identify Ostwald ripening as a key mechanism in mesogenic growth and establish the corona-forming block as an active regulator in liquid crystallization-driven self-assembly.

ABSTRACT The solution‐state aggregation of conjugated polymers critically determines the morphology and performance of organic solar cells (OSCs), yet processing optimization remains largely empirical. Here, we establish the sol–gel transition temperature ( T sol–gel ), determined by rheology, as a transferable descriptor linking solution aggregation to film formation and device performance. Using cryo‐electron microscopy (CEM), small‐angle neutron scattering (SANS), and rheology, we reveal that the high‐performance donor polymer D18 in chlorobenzene evolves from dissolved wormlike chains to a weak gel and then to a strong gel upon cooling. Importantly, processing near the T sol–gel temperature yields weak‐gel aggregates, which transform into a double fibril network during film formation, enabling enhanced charge transport, optimized phase separation, and uniform large‐area coating. Under this condition, D18:L8‐BO achieves a power conversion efficiency of 19.6% in small‐area devices and 17.1% in 17.6 cm 2 mini‐modules. More importantly, this T sol–gel ‐guided strategy is further validated in multiple conjugated polymers in OSCs, including PM6, PffBT4T‐2OD, and D18 processed from o ‐xylene, where the optimal performance consistently occurs near the corresponding sol–gel transition. These results identify weak‐gel pre‐aggregation near T sol–gel as a general processing window for constructing favorable fibrillar morphologies and provide a broadly applicable framework for morphology control in high‐performance OSCs.

Solid dispersion is a widely adopted formulation strategy to enhance the solubility of water-insoluble drugs. However, the molecular-level structural determinants of stability and dissolution behavior remain poorly understood. This study integrates Small-Angle Neutron Scattering (SANS) technology with coarse-grained molecular dynamics (CGMD) simulations to investigate the effects of preparation methods (melting vs solvent evaporation) and drug loadings (10%, 15%, 25%) on the microstructure and crystallinity of PXM-PEG solid dispersions. Deuterated PEG (d-PEG) is used in the SANS to enhance the scattering intensity in samples. The findings revealed that the lamellar thickness decreased significantly from 173.01 Å (pure d-PEG) to 44.12 Å (25% drug loading, melting method), while the d-spacing reduced from 71.13 to 36.65 Å, indicating a substantial disruption of the crystalline structure. Conversely, samples prepared by solvent evaporation maintained larger d-spacing (up to 93.27 Å at 10% drug loading) and more stable layer stacking (Nlayers ∼5.6), demonstrating higher structural order. The results indicate that the preparation method significantly influences the structural characteristics of the solid dispersions. The melting method yielded a higher amorphous content at low drug loadings, which is expected to improve drug solubility and bioavailability. In contrast, the solvent evaporation method tended to produce solid dispersions with higher crystallinity and uniform structures at higher drug loadings. SANS results indicated that samples prepared by the melting method exhibited higher disorder in the high-q region, while those prepared by the solvent evaporation method showed greater crystallinity. The CGMD simulations further elucidated the dynamic aggregation and structural formation of the drug and polymer molecules during the preparation process. In the melting simulations, drug and polymer molecules gradually aggregated into dense clusters, while in the solvent evaporation simulations, the aggregates grew larger and more asymmetrical as the solvent evaporated, ultimately forming ordered structures. The combined results from SANS and molecular dynamics simulations indicated the "sandwich-like" structure of PXM-PEG solid dispersions. The outcomes of this innovative approach have the potential to advance the development of solid dispersion formulations, enhance research and development efficiency, and pave the way for the industrial production of solid dispersions.