Surface Technology (表面技术)•2026•DOI: 10.16490/j.cnki.issn.1001-3660.2026.08.006
Laser cladding is a green surface modification technology widely used in aerospace and other high-end fields, but traditional process optimization methods such as single-variable analysis and orthogonal experiments suffer from low efficiency and high cost. The geometric characteristics of the cladding layer—dilution rate, forming coefficient, and wetting angle—directly determine service performance. Existing machine learning models often fail to achieve multi-objective optimization and comprehensive prediction. This study proposes a hybrid algorithm combining Grey Wolf Optimizer (GWO) with Backpropagation Neural Network (BPNN) to predict geometric quality indicators. Full-factorial single-track laser cladding experiments were conducted on 316L stainless steel with 316L alloy powder. A polynomial regression model predicted clad width and height with relative error below 4.2%. The GWO-BPNN model predicted dilution rate, forming coefficient, and wetting angle with an average coefficient of determination (R²) of 95.28%, a 12.4% improvement over traditional BPNN (82.93%). Experimental and inverse validation confirmed stable predictive performance across different parameter ranges, meeting engineering tolerance requirements. The method provides a quantitative basis for multi-dimensional optimization of cladding quality and demonstrates practical applicability in industrial scenarios.
Surface Technology (表面技术)•2026•DOI: 10.16490/j.cnki.issn.1001-3660.2026.09.004
Potassium dihydrogen phosphate (KH2PO4, KDP) crystals are indispensable optical components in high-power laser systems and inertial confinement fusion devices, yet their hygroscopicity, brittleness, and low hardness render them among the most difficult materials to machine. This study establishes a solid-phase chemical reaction rate model grounded in heterogeneous solid-phase reaction kinetics and the Arrhenius equation, quantifying the influence of mechanical action and temperature on reaction kinetics. The true contact area between the KDP crystal and the fixed abrasive pad is computed, and the reaction layer thickness is derived by coupling the reaction rate model with single-abrasive scratching theory. A material removal model is subsequently formulated, linking abrasive penetration depth to reaction layer thickness. Experiments were conducted at polishing pressures of 7.5, 15, 22.5, and 30 kPa and pad rotational speeds of 40, 50, 60, 70, and 80 r/min. Theoretical material removal rates were compared with empirical data, yielding discrepancies within 13% (maximum errors of 10.6% at 7.5 kPa and 12.5% at 30 kPa). Material removal rate increases monotonically with polishing pressure and pad rotational speed. The model elucidates the coupling mechanism between chemical and mechanical actions: solid-phase reactions generate a reaction layer on the workpiece surface, which is removed by abrasive mechanical action; equilibrium between chemical and mechanical actions enables high-quality KDP crystal processing.
Opto-Electronic Advances (光电进展)•2026•DOI: 10.29026/oea.2026.250224
Bound states in the continuum (BICs) have emerged as a central paradigm in nanophotonics, offering theoretically unbounded quality factors (Q) and topologically protected mode confinement within the radiative continuum. This review critically examines the trajectory of BIC research from foundational predictions by Wigner and von Neumann (1929) and semiconductor superlattice observations by Capasso et al. (1992) to contemporary metasurface implementations. We analyze design methodologies including machine learning and inverse design, and survey emergent BIC classes: super-BICs, chiral BICs, flatband BICs, and Moiré BICs. The integration of phase-change materials and liquid crystals enables dynamic control over emission and absorption, while strong light-matter interaction, ultrafast dynamics, and exceptional points are assessed for device relevance. Key application domains—lasing, optical sensing, and nonlinear optics—are evaluated with emphasis on conversion efficiency and sensitivity thresholds. We identify persistent challenges in fabrication tolerance, material loss, and scalable integration. The review concludes with perspectives on multilayer metasurfaces, quantum emitter interfacing, and pathways toward commercial BIC metadevices, providing a rigorous framework for researchers and engineers targeting high-performance photonic systems.
Opto-Electronic Advances (光电进展)•2026•DOI: 10.29026/oea.2026.250150
This study presents the first demonstration of a fast step heterodyne light-induced thermoelastic spectroscopy (SH-LITES) sensor utilizing a high-frequency quartz tuning fork (QTF) with a resonant frequency of approximately 100 kHz. The theoretical basis of heterodyne LITES (H-LITES) signal generation is analyzed, and an acetylene (C2H2) H-LITES sensor is constructed to evaluate performance. Comparative experiments between the high-frequency QTF and a standard commercial QTF (resonant frequency ~32.768 kHz) reveal that the high-frequency QTF achieves a tenfold faster response time, with a measurement cycle of 33 ms—90% shorter than commercial counterparts. The proposed SH-LITES technique further reduces the scanning time to 15 ms, representing the shortest LITES measurement time reported to date. To validate dynamic gas detection capabilities, an H2O-LITES system integrating both QTF types is employed for real-time monitoring of H2O concentration during various respiration patterns. Results demonstrate that SH-LITES more accurately captures rapid H2O concentration fluctuations during respiration, outperforming the commercial QTF-based H-LITES sensor in fast-response scenarios. These findings establish a new benchmark for high-speed trace gas sensing with potential applications in combustion diagnostics, healthcare monitoring, and environmental surveillance.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2026•DOI: 10.1088/1674-4926/25060003
Chemical mechanical polishing (CMP) is indispensable for global planarization in semiconductor manufacturing, particularly as integrated circuit technology advances to sub-7 nm nodes where atomic-level surface flatness is critical. Silica abrasives constitute over 90% of the abrasive market in advanced CMP processes, operating via a chemical-mechanical synergistic mechanism: chemical softening of the wafer surface followed by mechanical removal of the softened layer, repeated to achieve planarization. Despite their prevalence, conventional silica abrasives face persistent challenges: relatively low material removal rate (MRR), agglomeration leading to poor dispersion and surface defects, and limitations in achieving ultimate surface uniformity. This review systematically summarizes six decades of progress in silica abrasives for CMP, tracing development from simple spherical particles to complex structural designs (mesoporous, hollow, raspberry-shaped) that enhance slurry transport and mechanical action. Surface chemical modifications (amino or polymer groups) improve dispersion stability and reduce scratching. Composites with ceria or polymers and precise control of particle size distribution are key to performance enhancement. State-of-the-art slurries achieve surface roughness below 0.1 nm RMS. Emerging directions emphasize sustainability and smart manufacturing, notably biodegradable abrasives that disintegrate after use, simplifying post-CMP cleanup and minimizing environmental impact, aligning with green manufacturing principles. This review provides theoretical insights and forward-looking strategies to overcome current limitations and advance CMP abrasives toward next-generation semiconductor manufacturing.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01946-3
Photo-assisted lithium–sulfur batteries (PALSBs) offer an eco-friendly solution to address the issue of sluggish reaction kinetics of conventional LSBs. However, designing an efficient photoelectrode for practical implementation remains a significant challenge. Herein, we construct a free-standing polymer–inorganic hybrid photoelectrode with a direct Z-scheme heterostructure to develop high-efficiency PALSBs. Specifically, polypyrrole (PPy) is in situ vapor-phase polymerized on the surface of N-doped TiO2 nanorods supported on carbon cloth (N-TiO2/CC), thereby forming a well-defined p–n heterojunction. This architecture efficiently facilitates the carrier separation of photo-generated electron–hole pairs and significantly enhances carrier transport by creating a built-in electric field. Thus, the PPy@N-TiO2/CC can simultaneously act as a photocatalyst and an electrocatalyst to accelerate the reduction and evolution of sulfur, enabling ultrafast sulfur redox dynamics, as convincingly validated by both theoretical simulations and experimental results. Consequently, the PPy@N-TiO2/CC PALSB achieves a high discharge capacity of 1653 mAh g−1, reaching 98.7% of the theoretical value. Furthermore, 5 h of photo-charging without external voltage enables the PALSB to deliver a discharge capacity of 333 mAh g−1, achieving dual-mode energy harvesting capabilities. This work successfully integrates solar energy conversion and storage within a rechargeable battery system, providing a promising strategy for sustainable energy storage technologies.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01816-y
Optical synapses have an ability to perceive and remember visual information, making them expected to provide more intelligent and efficient visual solutions for humans. As a new type of artificial visual sensory devices, photoelectric memristors can fully simulate synaptic performance and have great prospects in the development of biological vision. However, due to the urgent problems of nonlinear conductance and high-energy consumption, its further application in high-precision control scenarios and integration is hindered. In this work, we report an optoelectronic memristor with a structure of TiN/CeO2/ZnO/ITO/Mica, which can achieve minimal energy consumption (187 pJ) at a single pulse (0.5 V, 5 ms). Under the stimulation of continuous pulses, linearity can be achieved up to 99.6%. In addition, the device has a variety of synaptic functions under the combined action of photoelectric, which can be used for advanced vision. By utilizing its typical long-term memory characteristics, we achieved image recognition and long-term memory in a 3×3 synaptic array and further achieved female facial feature extraction behavior with an activation rate of over 92%. Moreover, we also use the linear response characteristic of the device to design and implement the night meeting behavior of autonomous vehicles based on the hardware platform. This work highlights the potential of photoelectric memristors for advancing neuromorphic vision systems, offering a new direction for bionic eyes and visual automation technology.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01728-x
Enhancing the firefighting protective clothing with exceptional thermal barrier and temperature sensing functions to ensure high fire safety for firefighters has long been anticipated, but it remains a major challenge. Herein, inspired by the human muscle, an anisotropic fire safety aerogel (ACMCA) with precise self-actuated temperature monitoring performance is developed by combining aramid nanofibers with eicosane/MXene to form an anisotropically oriented conductive network. By combining the two synergies of the negative temperature-dependent thermal conductive eicosane, which induces a high-temperature differential, and directionally ordered MXene that establishes a conductive network along the directional freezing direction. The resultant ACMCA exhibited remarkable thermoelectric properties, with S values reaching 46.78 μV K−1 and κ values as low as 0.048 W m−1 K−1 at room temperature. Moreover, the prepared anisotropic aerogel ACMCA exhibited electrical responsiveness to temperature variations, facilitating its application in intelligent temperature monitoring systems. The designed anisotropic aerogel ACMCA could be incorporated into the firefighting clothing as a thermal barrier layer, demonstrating a wide temperature sensing range (50–400 °C) and a rapid response time for early high-temperature alerts (~1.43 s). This work provides novel insights into the design and application of temperature-sensitive anisotropic aramid nanofibers aerogel in firefighting clothing.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01693-5
Photonic computing has emerged as a promising technology for the ever-increasing computational demands of machine learning and artificial intelligence. Due to the advantages in computing speed, integrated photonic chips have attracted wide research attention on performing convolutional neural network algorithm. Programmable photonic chips are vital for achieving practical applications of photonic computing. Herein, a programmable photonic chip based on ultrafast laser-induced phase change is fabricated for photonic computing. Through designing the ultrafast laser pulses, the Sb film integrated into photonic waveguides can be reversibly switched between crystalline and amorphous phase, resulting in a large contrast in refractive index and extinction coefficient. As a consequence, the light transmission of waveguides can be switched between write and erase states. To determine the phase change time, the transient laser-induced phase change dynamics of Sb film are revealed at atomic scale, and the time-resolved transient reflectivity is measured. Based on the integrated photonic chip, photonic convolutional neural networks are built to implement machine learning algorithm, and images recognition task is achieved. This work paves a route for fabricating programmable photonic chips by designed ultrafast laser, which will facilitate the application of photonic computing in artificial intelligence.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-05-04)
Hard carbons (HCs) are recognized as potential anode materials for sodium-ion batteries (SIBs) because of their low cost, environmental friendliness, and the abundance of their precursors. The presence of graphitic domains, numerous pores, and disordered carbon layers in HCs plays a significant role in determining their sodium storage ability, but these structural features depend on the precursor used. The influence of functional groups, including heteroatoms and oxygen-containing groups, and the microstructure of the precursor on the physical and electrochemical properties of the HC produced are evaluated, and the effects of carbonization conditions (carbonization temperature, heating rate and atmosphere) are also discussed.
Journal of Semiconductors (半导体学报 - 中国科学院半导体研究所)•2025•DOI: 10.1088/1674-4926/25010010
Infrared and terahertz waves constitute pivotal bands within the electromagnetic spectrum, distinguished by their robust penetration capabilities and non-ionizing nature. These wavebands offer the potential for achieving high-resolution and non-destructive detection methodologies, thereby possessing considerable research significance across diverse domains including communication technologies, biomedical applications, and security screening systems. Two-dimensional materials, owing to their distinctive optoelectronic attributes, have found widespread application in photodetection endeavors. Nonetheless, their efficacy diminishes when tasked with detecting lower photon energies. Furthermore, as the landscape of device integration evolves, two-dimensional materials struggle to align with the stringent demands for device superior performance. Topological materials, with their topologically protected electronic states and non-trivial topological invariants, exhibit quantum anomalous Hall effects and ultra-high carrier mobility, providing a new approach for seeking photosensitive materials for infrared and terahertz photodetectors. This article introduces various types of topological materials and their properties, followed by an explanation of the detection mechanism and performance parameters of photodetectors. Finally, it summarizes the current research status of near-infrared to far-infrared photodetectors and terahertz photodetectors based on topological materials, discussing the challenges faced and future prospects in their development.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.01.005
The combination of ultrasonic and acid fracturing fluid can strengthen the modification effect on the micropore structure of the coal matrix, thereby enhancing the efficiency of the acid fracturing process. In this research, acetic acid was utilized to formulate acid fracturing fluids with varying concentrations, and the evolutionary traits of both the acid fracturing fluids and ultrasonic waves in relation to coal samples were investigated. The functional group structure, mineral composition, micropore structure and surface morphology of coal samples were characterized by FTIR, XRD, N2 adsorption at low temperature and SEM-EDS. The results showed that aromatics (I) and branching parameters (CH2/CH3) were reduced by 81.58% and 88.67%, respectively, after 9% acetic acid treatment. Acetic acid can dissolve carbonates and clay minerals in coal, create new pores, and increase porosity, pore volume and pore fractal dimension. After modification by 7% acetic acid, the pore volume increased by 5.7 times. SEM observation shows that the diameter of coal surface holes increases, EDS scanning shows that the content of mineral elements in coal decreases, the connectivity of coal holes increases, and the holes expand. The findings of this research offer theoretical direction for optimizing ultrasonic-enhanced acid fracturing fluid modification.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.02.001
Lunar core samples are the key materials for accurately assessing and developing lunar resources. However, the difficulty of maintaining borehole stability in the lunar coring process limits the depth of lunar coring. Here, a strategy of using a reinforcement fluid that undergoes a phase transition spontaneously in a vacuum environment to reinforce the borehole is proposed. Based on this strategy, a reinforcement liquid suitable for a wide temperature range and a high vacuum environment was developed. A feasibility study on reinforcing the borehole with the reinforcement liquid was carried out, and it is found that the cohesion of the simulated lunar soil can be increased from 2 to 800 kPa after using the reinforcement liquid. Further, a series of coring experiments are conducted using a self-developed high vacuum (vacuum degree of 5 Pa) and low-temperature (between −30 and 50 ℃) simulation platform. It is confirmed that the high-boiling-point reinforcement liquid pre-placed in the drill pipe can be released spontaneously during the drilling process and finally complete the reinforcement of the borehole. The reinforcement effect of the borehole is better when the solute concentration is between 0.15 and 0.25 g/mL.
China Foundry•2025•DOI: 10.1007/s41230-025-4267-y
Al-based TiC particle-reinforced composites with varying TiC concentrations were fabricated through semi-continuous casting. The effects of TiC particles on the alloys’ microstructure, grain boundary segregation, and mechanical properties were systematically analyzed. Moreover, the mechanisms by which TiC particles contribute to grain refinement, suppression of grain boundary segregation, and enhancement of hardness and wear resistance were discussed. The results demonstrate that TiC particles act as heterogeneous nucleation sites for α-Al within the Al-Cu-Mn alloys, leading to a refinement of grain size. As the TiC particle’s content increases, the grain size of the alloy drops at first and then elevates, transitioning from coarse dendritic crystals to fine equiaxed grains. At a TiC content of 1.3wt.%, the alloy exhibits the smallest grain size, reducing from 139±42 μm without TiC to 90±38 μm. Beyond this concentration, grain coarsening is observed. The incorporation of TiC particles effectively mitigates Cu segregation at grain boundaries, thereby enhancing the homogeneity of the Al-Cu-Mn matrix alloys. Additionally, the addition of TiC particles promotes hardness and wear resistance. Both hardness and wear resistance exhibit an initial increase followed by a decrease with increasing TiC content from 0 to 1.8wt.%.
China Foundry•2025•DOI: 10.1007/s41230-025-4017-1
Effects of solution and aging treatment on the microstructure and mechanical properties of a novel Al-Zn-Mg-Cu alloy by microalloying rare elements Sc and Er were studied. The results show that solution time has a visible influence on the microstructure and mechanical properties of the alloy. Specifically, as the solution time increases, the area fraction of the residual phase in the alloy decreases, and the shape of the grain becomes more spheroidal and coarser, leading to a decrease in hardness. This is attributed to the dissolution of strengthening phases during the solution treatment, which weakens the solid solution strengthening effect. The single-stage aging treatment shows an initial increase in strength and hardness of the alloy, followed by a decrease as the aging time is extended, until a steady state is achieved. The optimal single-aging conditions are found to be at 120 °C for 24 h, where the alloy exhibits an excellent combination of high strength and good ductility, with an ultimate tensile strength (UTS) of 523 MPa, yield strength (YS) of 482 MPa, and elongation (El) of 1.75%, respectively. Compared to single-stage aging, double-stage aging (120 °C for 24 h and then 150 °C for 52 h) significantly increases the elongation of the alloy (4.17%), but the UTS reduces to 465.29 MPa, and YS reduces to 410.64 MPa. Transmission electron microscopy (TEM) observations disclose that the grain size, the distribution spacing of precipitates along the grain boundary, and the width of the precipitation-free zone (PFZ) all undergo augmentation as the duration of the second stage aging process elongates.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3093-y
To satisfy the demand for low-cost and long-range electric vehicles by the market, the commercialization of ultrahigh nickel cathode materials with high specific capacity and a wide electrochemical window is expected to facilitate the development of lithium-ion batteries. However, residual lithium compounds with a strong alkalinity cause difficulty in cathode preparation and indirectly affect the cycling stability of the cathode during cycling. Given the inevitability of the formation of residual alkali, a lithium-borate coating with an adjustable thickness was selected by controlling the formation of residual alkali. An additional lithium source was added to the synthesis process and converted into a thicker and more complete coating structure, which rendered the cathode with better cycle stability. As a result, the percentage of peak area of lithium carbonate on the surface-modified cathode surface exhibited a considerable decrease from 38.07% to 28.26%. The etching results show the formation of a uniform coating layer after boric acid treatment. The initial capacity of the treated cathode was 214.6 mAh·g−1 owing to the favorable effect of the surface coating, and the capacity retention raised from 59.35% to 90.75% and from 63.81% to 91.94% after cycling at 0.5 and 1 C current densities, respectively. The boric acid coating-modified strategy proposed in this paper considerably ameliorates the cycling stabilization of cathodes and provides superior commercial application value for ultrahigh nickel cathode materials.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6065-5
Arching and cracking of joints between slabs have become a problem in China Railway Track System (CRTS) II slab track. The slab track is susceptible to complex temperature variations as a longitudinal continuous structure. Based on measured data, a thermal-mechanical coupling model of the track was established. The deformation characteristics and interfacial damage behavior of joints under typical temperature fields were studied. The findings indicate that the annual extreme temperature range of the slab track, fluctuates from −1.4 to 49.8 ℃. The annual temperature gradient within the vertical depth range of 0 to 0.2 m of the track varies between −16.19 ℃/m and 30.15 ℃/m. The vertical deformation of joints is significantly influenced by high temperatures, with a maximum measured deformation of 0.828 mm. The joint seams are primarily affected by low temperatures, which lead to a separation of 0.9 to 1.0 mm. Conversely, interlayer damage of joints is predominantly influenced by elevated temperatures. In summer, the maximum ratio of interface damage area in the joint can reach up to 95%, with the maximum debonding area ratio can be as high as 84%. The research results can provide help for joint damage regularity and deformation control of CRTS II slab track.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3071-9
Indigenous microbial communities were employed after subculture in stirred and column bioleaching experiments involving ion-adsorption type rare earth ore. The microbial eukaryotic communities exhibited dramatically varying diversity and structure across culture compositions. Compared with Czapek and sucrose medium, the community cultured in a nutrient broth (NB) medium had a higher diversity, and it was mainly composed of Zygosaccharomyces, Ustilago, Kodamaea, Malassezia, and Aspergillus. These microorganisms secrete organic acids, such as citric acid, malic acid, gluconic acid, and itaconic acid, which provide effective coordination electrons through hydroxyl and carboxyl groups. Stirred bioleaching experiments were conducted to investigate the effect of community, inoculum dosage, liquid–solid ratio, and time on the leaching efficiency. Stirred bioleaching resulted in a concentration limitation phenomenon. When the inoculum dosage of the community cultured in NB medium was 70vol%, the liquid–solid ratio was 5.0 mL·g−1, and the time was 60 min, the upward trend of rare earths leaching rate has become very small. Specifically, the leaching rates of detectable La, Ce, and Y were approximately 92.49%, 92.42%, and 94.39%, respectively. The leaching efficiency and the three influencing factors all conformed to the Poly5 polynomial function, with variances above 0.99. Column bioleaching experiments were performed at a scale of 1 kg. The self-propelled low-pH environment increased the leaching efficiency, which resulted in a leaching rate of 98.88% for rare earths after 117 h. X-ray diffraction and scanning electron microscopy revealed that the samples mainly comprised quartz, kaolinite, orthoclase, muscovite, and zeolite, which were predominantly present in the form of lumps, flakes, rods, and small particles. After bioleaching, the wave intensity of quartz, kaolinite, orthoclase, and muscovite increased, and that of zeolite decreased considerably. A diminution in the number of fine particles indicated the dissolution of small quantities of clay minerals. Ultimately, the differentiated bioleaching mechanism of various forms of rare earths was discussed based on experimental phenomena.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01355-y
This paper proposes virtual impedance adaptation of the lower-limb exoskeleton for human performance augmentation (LEHPA) based on deep reinforcement learning (VIADRL) to mitigate reliance on model accuracy and address the ever-changing human-exoskeleton interaction (HEI) dynamics. The classical sensitivity amplification control strategy is expanded to the virtual impedance control strategy with more learnable virtual impedance parameters. The adjustment of these virtual impedance parameters is formalized as finding the optimal policy for a Markov Decision Process and can then be effectively resolved using deep reinforcement learning algorithms. To ensure safe and efficient policy training, a multibody simulation environment is established to facilitate the training process, supplemented by the innovative hybrid inverse-forward dynamics simulation approach for executing the simulation. For comparison purposes, the SADRL strategy is introduced as a benchmark. A novel control performance evaluation method based on the HEI forces at the back, thighs, and shanks is proposed to quantitatively evaluate the performance of our proposed VIADRL strategy. The VIADRL controller is systematically compared with the SADRL controller at five selected walking speeds. The lumped ratio of HEI forces under the SADRL strategy relative to those under the SADRL strategy is as low as 0.81 in simulation and approximately 0.89 on the LEHPA prototype. The overall reduction of HEI forces demonstrates the superiority of the VIADRL strategy in comparison to the SADRL strategy.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01188-9
Microneedle (MN) is a medical device containing an array of needles with a micrometer-scale. It can penetrate the human stratum corneum painlessly and efficiently for treatment and diagnosis purposes. Currently, the materials commonly used to manufacture MNs include silicon, polymers, ceramics and metals. Metallic MNs (MMNs) have drawn significant attention owing to its superior mechanical properties, machinability, and biocompatibility. This paper is a state-of-the-art review of the structure, fabrication technologies, and applications of MMNs. According to the relative position of the axis of MN and the plane of the substrate, MMNs can be divided into in-plane and out-of-plane. Solid, hollow, coated and porous MMNs are also employed to characterize their internal and surface structures. Until now, numerous fabrication technologies, including cutting tool machining, non-traditional machining, etching, hot-forming, and additive manufacturing, have been used to fabricate MMNs. The recent advances in the application of MMNs in drug delivery, disease diagnosis, and cosmetology are also discussed in-depth. Finally, the shortcomings in the fabrication and application of MMNs and future directions for development are highlighted.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6107-z
Molybdenum tailings are the solid waste left from ore processing, which damages soil and water resources. To address that, molybdenum tailings (MTs) powder obtained from molybdenum tailings sands was processed as an admixture. Compared with moisture-cured conditions, the influence of MTs on the steam-cured mortar’s mechanical properties, surface and internal pore characteristics, and microscopic morphology was investigated. The results show that steam-cured mortar containing appropriate MTs can still have high early strength. When the content of MTs doesn’t exceed 15%, the mechanical strength of mortar steam-cured for 3 d can reach 85% of that of corresponding mortar moisture-cured for 28 d, and that of mortar steam-cured for 28 d isn’t lower than 90% of that of pure cement mortar. The proportion of harmful pores (HFP) and more harmful pores (MHFP) and most probable pore diameters (MPD) on the mortar surface containing MTs steam-cured for 28 d are significantly decreased. When MTs’ content is 15%, the proportion of HFP and MHFP on the surface of paste is decreased by 71.4% and 72.2%, respectively, with MPS decreasing from 12.7 nm to 10.8 nm. SEM analysis shows that the surfaces of steam-cured paste containing 15% MTs have more hydration products and dense microstructures. The effect of pozzolanic and dense filling of MTs effectively refines the pore structure, reducing the large pore-size pores.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-5929-z
High-entropy alloy composites (HEACs) have attracted significant attention due to their exceptional mechanical properties and chemical stability. By adjusting the content of reinforcing particles in the high-entropy alloy and by employing advanced additive manufacturing techniques, high-performance HEACs can be fabricated. However, there is still considerable room for improvement in their performance. In this study, CoCrFeMnNi HEA powders were used as the matrix, and NiCoFeAlTi high-entropy intermetallic powders were used as the high-entropy reinforcement (HER). CoCrFeMnNi/NiCoFeAlTi HEACs were fabricated using selective laser melting technology. The study results indicate that after aging, the microstructure of HEACs with HER exhibits Al- and Ti-rich nano-oxide precipitates with an orthorhombic CMCM type structure system. After aging at 873 K for 2 h, HEACs with HER achieved excellent overall mechanical properties, with an ultimate tensile strength of 731 MPa. This is attributed to the combined and synergistic effects of precipitation strengthening, dislocation strengthening, and the high lattice distortion caused by high intragranular defects, which provide a multi-scale strengthening and hardening mechanism for the plastic deformation of HEACs with HER. This study demonstrates that aging plays a crucial role in controlling the precipitate phases in complex multi-element alloys.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3133-7
Electrochemical CO2 reduction is a sustainable method for producing fuels and chemicals using renewable energy sources. Sn is a widely employed catalyst for formate production, with its performance closely influenced by the catalyst ink formulations and reaction conditions. The present study explores the influence of catalyst loading, current density, and binder choice on Sn-based CO2 reduction systems. Decreasing catalyst loading from 10 to 1.685 mg·cm−2 and increasing current density in highly concentrated bicarbonate solutions significantly enhances formate selectivity, achieving 88% faradaic efficiency (FE) at a current density of −30 mA·cm−2 with a cathodic potential of −1.22 V vs. reversible hydrogen electrode (RHE) and a catalyst loading of 1.685 mg·cm−2. This low-loading strategy not only reduces catalyst costs but also enhances surface utilization and suppresses the hydrogen evolution reaction. Nafion enhances formate production when applied as a surface coating rather than pre-mixed in the ink, as evidenced by improved faradaic efficiency and lower cathodic potentials. However, this performance still does not match that of binder-free systems because Sn-based catalysts intrinsically exhibit high catalytic activity, making the binder contribution less significant. Although modifying the electrode surface with binders leads to blocked active sites and increased resistance, polyvinylidene fluoride (PVDF) remains promising because of its stability, strength, and conductivity, achieving up to 72% FE to formate at −30 mA·cm−2 and −1.66 V vs. RHE. The findings of this research reveal methodologies for optimizing the catalyst ink formulations and binder utilization to enhance the conversion of CO2 to formate, thereby offering crucial insights for the development of a cost-efficient catalyst for high-current-density operations.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3035-0
Electrochemical metallurgy at low temperature (<473 K) shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner. However, the kinetics of the electrodeposition process is generally slow at low temperature, resulting in large overpotential and low current efficiency. Thus, the application of external physical fields has emerged as an effective strategy for improving the mass and charge transfer processes during electrochemical reactions. This review highlights the challenges associated with low-temperature electrochemical processes and briefly discusses recent achievements in optimizing electrodeposition processes through the use of external physical fields. The regulating effects on the optimization of the electrodeposition process and the strategies for selecting various external physical fields, including magnetic, supergravity, and ultrasonic fields are summarized from the perspectives of equipment and mechanisms. Finally, advanced methods for in-situ characterization of external physical field-assisted electrodeposition processes are reviewed to gain a deeper understanding of metallic electrodeposition. An in-depth exploration of the mechanism by which external physical fields affect the electrode process is essential for enhancing the efficiency of metal extraction at low temperatures.