Surface Technology (表面技术)•2026•DOI: 10.16490/j.cnki.issn.1001-3660.2026.11.006
Gear transmissions under high-speed and heavy-load conditions frequently fail due to incomplete lubricating films, leading to scuffing and severe wear. This study introduces elliptical micro-textures on gear tooth surfaces to enhance hydrodynamic lubrication. A CFD model, based on the Navier-Stokes equations with an incompressible Newtonian fluid assumption, simulated the effects of area ratio (δ), ellipticity (γ=rb/ra), inclination angle (θ), major axis radius (ra), and depth (h) on dimensionless load capacity (W*), wall friction force (F*), and dynamic pressure coefficient (K=W*/F*). Orthogonal rolling-sliding wear tests on cylindrical rollers validated the simulations. Results indicate that area ratio and inclination angle are the most influential parameters, with optimal ranges of 25%-30% and 45°, respectively. The optimal texture parameters were identified as h=20 μm, ra=150 μm, γ=0.7, and θ=0°. Gear tests with these optimized textures showed a transition from severe adhesive wear to minor scratching, with maximum and minimum damage area ratios reduced by 81.11% and 76.97%, respectively, compared to untextured gears. The study acknowledges limitations due to isothermal, incompressible assumptions and neglect of thermal effects, surface elastic deformation, and cavitation. Future work aims to develop a thermo-elastohydrodynamic lubrication model incorporating operating parameters for precise prediction under extreme conditions.
Surface Technology (表面技术)•2026•DOI: 10.16490/j.cnki.issn.1001-3660.2026.12.007
The corrosion resistance of ASTM A182 F347 austenitic stainless steel was enhanced via a two-stage surface engineering protocol: plasma transferred arc deposition of Stellite 6 (STL6) followed by chemical vapor deposition of titanium nitride (TiN). Microstructural characterization confirmed a metallurgically bonded interface with elemental interdiffusion; the STL6 layer exhibited a graded structure from planar/equiaxed grains at the substrate to columnar dendrites and fine equiaxed grains at the surface, with minimal oxide content. Electrochemical testing in 3.5% NaCl solution revealed that the STL6/TiN composite coating reduced the corrosion current density to 0.37 μA/cm², the lowest among the three sample types (F347 substrate, F347-STL6, and F347-STL6-TiN). The composite coating also demonstrated the highest passivation potential (939 mV) and the largest impedance modulus |Z|, indicating superior passive film stability. Post-corrosion analysis showed that the F347 substrate suffered extensive deep pitting, while the STL6 coating exhibited intergranular corrosion with an oxide film. In contrast, the STL6/TiN composite coating displayed only sparse shallow pits. The improved performance is attributed to the formation of a dense Cr₂O₃ passive film on the STL6 layer and the additional barrier provided by the TiN topcoat. These findings offer a viable route for extending the service life of F347 stainless steel in aggressive environments.
Nano Research•2026•DOI: 10.26599/NR.2026.94908686
Corrosion and icing critically threaten the service safety of magnesium (Mg) alloys in aerospace and transportation industries. Although superhydrophobic coatings offer effective anti-corrosion and anti-icing functions, they are limited by susceptibility to failure due to physical damage or capillary condensation. Here, a multifunctional integrated coating (SAAS) is reported, which endows coated Mg alloys with excellent superhydrophobicity, active anti-corrosion performance, anti-icing properties, and fast self-healing capabilities. Layered double hydroxide (LDH) modified and intercalated with sodium laurate (La) acts as nanoreservoirs, releasing La corrosion inhibitors via an anion-exchange process to retard corrosion. Incorporation of MXene provides full-spectrum high absorption and efficient photothermal conversion, achieving a surface temperature of 61 °C under 1.0 sun illumination, which prevents adhesion and accumulation of supercooled droplets. Near-infrared (NIR) irradiation induces macromolecular chain migration and phase transition, enabling fast self-healing of coating damage. The SAAS coating exhibits a water contact angle of 153°, a corrosion current density of 1.294 × 10⁻⁹ A·cm⁻² (four orders of magnitude lower than bare Mg alloy), an icing delay time approximately 23 times longer than the substrate, and a healing rate of about 0.34 cm·s⁻¹ under NIR. This study provides a novel strategy for enhancing aircraft skin durability and offers insights into multifunctional coating design.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2026•DOI: 10.1016/j.ijmst.2026.02.006
The development of efficient CO2 adsorbents is critical for achieving net-zero targets. MgO represents a promising solid adsorbent for CO2 capture, yet its limited specific surface area and insufficient active sites restrict its adsorption capacity under moderate temperature conditions. A rod-like anhydrous MgCO3 precursor was hydrothermally synthesized and calcined at 500 °C for 3 h to obtain porous MgO (184.9 m2 g−1, 0.38 cm3/g), which was then modified with 20% NaNO2 (by mole) via impregnation. This adsorbent achieved an adsorption capacity of 12.6 mmol g−1 after 120 min under a pure CO2 atmosphere at 325 °C. Comprehensive characterization reveals that NaNO2 modification leads to the NaNO3 and Na2CO3 formation on the MgO surface during calcination. The introduced NaNO3 effectively promotes oxygen vacancy formation, while the generated Na2CO3 serves as heterogeneous nucleation sites, collectively reducing the reaction energy barrier and enhancing interfacial mass transfer. This synergistic effect facilitates the MgCO3 formation followed by its conversion to the thermodynamically more stable Na2Mg(CO3)2. Kinetic studies elucidate that adsorption is dominated by surface chemical reactions and diffusion mechanisms at different stages. These fundamental insights into the adsorption mechanisms of nitrite-modified MgO provide valuable guidance for the rational design of advanced MgO-based CO2 adsorbents with enhanced performance.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2026•DOI: 10.1016/j.ijmst.2026.03.004
The energy-driven progressive brittle shear failure of rock joints is a key mechanism behind deep engineering disasters such as joint-induced rockbursts and engineering earthquakes. To investigate the energy evolution mechanisms and disaster proneness, monotonic and stepwise loading-unloading tests were performed on regular dentate joints under constant normal stiffness boundary conditions. Results indicate a transition in damage mechanism from climbing wear of low-inclination asperities to brittle rupture of high-inclination ones, accompanied by a marked decrease in irreversible displacement. Energy analysis reveals a strong linear relationship between pre-peak elastic energy density and both input energy density and shear stress squared. The post-peak elastic energy release rate (g) and the self-sustaining instability coefficient (l) increase with joint undulation. A dimensionless brittleness index (BI) integrating the complete energy conversion and release process was proposed to quantify the energy balanced budget. The highly undulated joint R4 showed the most pronounced brittleness and instability intensity with the highest BI value of 0.697, along with g = 0.774 and l = 0.611. This study provides deeper insight into the understanding of the disaster-inducing proneness and stability assessment in jointed rock mass.
China Foundry•2026•DOI: 10.1007/s41230-026-5097-2
High Al content inhibits the formation of B2 phase, which improves creep resistance in high Al/Nb-containing TiAl alloys. In this work, the microstructure evolution and creep behavior of TiAl based alloy Ti-46Al-8Nb (at.%) with a high Al/Nb content, produced by the vacuum consumable electrode melting technology and the electromagnetic cold crucible melting technology, were studied. The microstructure of the Ti-46Al-8Nb alloy is composed of α2/γ phases arranged in layers with different orientations, which possesses smooth grain boundaries due to small-blocky segregation and irregular serrated grain boundaries caused by large-blocky segregation. Under conditions of 780-820 °C and 125-175 MPa for 200 h, it exhibits typical power-law creep characteristics. The apparent activation energy of creep (Q) and apparent stress exponent (n) of the Ti-46Al-8Nb alloy are Q=274 kJ·mol-1 and n=1.97, respectively. The creep deformation mechanism is grain boundary sliding. Cracks easily form at the smooth boundary. The irregular serrated boundaries with small specific surface area hinder the dislocation movement, thereby improving the boundary creep resistance. When the stress concentration reaches a certain degree, the cracks will initiate between the lamellar structures within the grain. The crack usually propagates along the boundary perpendicular to or at an angle of 45° with the stress axis until creep failure occurs.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01840-y
Flexible fiber sensors, with their excellent wearability and biocompatibility, are essential components of flexible electronics. However, traditional methods face challenges in fabricating low-cost, large-scale fiber sensors. In recent years, the thermal drawing process has rapidly advanced, offering a novel approach to flexible fiber sensors. Through the preform-to-fiber manufacturing technique, a variety of fiber sensors with complex functionalities spanning from the nanoscale to kilometer scale can be automated in a short time. Examples include temperature, acoustic, mechanical, chemical, biological, optoelectronic, and multifunctional sensors, which operate on diverse sensing principles such as resistance, capacitance, piezoelectricity, triboelectricity, photoelectricity, and thermoelectricity. This review outlines the principles of the thermal drawing process and provides a detailed overview of the latest advancements in various thermally drawn fiber sensors. Finally, the future developments of thermally drawn fiber sensors are discussed.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6210-9
The accuracy of wheel-rail rolling contact force is of great significance for vehicle dynamics simulation. A wheel-rail rolling contact behavior model considering wheelset yaw is proposed. The NORM algorithm is adopted to solve the wheel-rail normal contact problem. The extended creep force model (ECF) is used for the tangential contact problem, which considers different interfacial conditions, temperature in the contact area, and the elastoplastic behavior of the third body. A fatigue life prediction framework based on the critical plane method is introduced to evaluate the contact fatigue damage under the coupled influence of yaw angle and interfacial conditions. The effects of wheel yaw angle on the contact pressure and wheel-rail rolling contact fatigue life under dry and wet conditions are investigated. The results show that under both dry and wet conditions, increasing yaw angle leads to an increase in creepage, expansion of the sliding area, enhancement of creep force, and a simultaneous increase in the contact area temperature, thereby causing an increase in the fatigue parameter (FP). The wheel-rail rolling contact life with yaw angle is shortened compared to that without yaw, and the life decay rate under wet condition is slower than that under dry condition.
Nano-Micro Letters•2026•DOI: 10.1007/s40820-025-01994-9
Electrolytic Zn–MnO2 batteries are promising candidates for safe and sustainable energy storage owing to their high voltage, environmental benignity, and cost-effectiveness. However, practical applications are hindered by the poor conductivity and the irreversible dissolution of conventional ε-MnO2 deposits. Herein, we report a scalable semisolid slurry electrode architecture that enables stable MnO2 deposition/dissolution using a three-dimensional percolating network of carbon nanotubes (CNTs) as both conductive matrix and deposition host. The slurry system promotes the formation of highly conductive γ-MnO2 owing to enhanced charge transfer kinetics, enabling overall dissolution rather than the localized separation typically seen in traditional electrodes. The Zn–MnO2 slurry cell exhibits a reversible areal capacity approaching 60 mAh cm−2. Moreover, the flowable nature of the slurry allows electrochemically inactive MnO2 formed during dissolution to be reconnected and reactivated by CNTs in the rheological network, ensuring deep utilization and cycling stability. This work establishes a slurry electrode strategy to improve electrolytic MnO2 reactions and offers a viable pathway toward renewable aqueous batteries for grid-scale applications.
Journal of Central South University•2026•DOI: 10.1007/s11771-026-6235-0
The flotation separation of high pyrite content secondary copper ores faces challenges including elevated pH levels, poor xanthate selectivity, and higher costs associated with its combination with Z-200. In this work, a composite thionocarbamate collector (TJ-215), with low-cost raw materials and a short synthetic route, showed a better selectivity for chalcocite than Z-200 when pH>8. Zeta potential analysis indicated a stronger interaction between TJ-215 and chalcocite. These results were achieved through the synergistic coordination of NH—C=S and C=N—OH in TJ-215 molecule, compared with the single thiourea group, NH—C=S, in Z-200 molecule. At low-alkaline condition, the NH—C=S in TJ-215 formed Cu—S, Cu—N bonds with Cu atoms, and the C=N—OH combined with Cu to form a Cu—O bond. The results of this study provide guidance on the replacement of Z-200 by TJ-215 in the separation of chalcocite from pyrite in weak alkaline conditions.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01789-y
Immunization has long played essential roles in preventing diseases. However, the desire for precision delivery of vaccines to boost a robust immune response remains largely unmet. Here, we describe the use of acupoint delivery of nanovaccines (ADN) to elicit dual-niche immunological priming. ADN can simultaneously stimulate mast cell-assisted maturation of dendritic cells at the acupoint and enable direct delivery of nanovaccines into the draining lymph nodes. We demonstrate that ADN not only provokes antigen presentation by lymph node-resident CD8α+ dendritic cells, but also induces the accumulation of nanovaccines in B-cell zones, amplifying antigen-specific cytotoxic T lymphocyte responses and immunoglobulin G antibody expression in draining lymph nodes. ADN also generates systemic immune responses by causing immune memory and preventing T-cell anergy in the spleen. Further supported by evoking effective antitumor responses and high-level antiviral antibodies in mice, ADN provides a simple yet versatile platform for advanced nanovaccination.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01787-0
Neuromorphic devices have shown great potential in simulating the function of biological neurons due to their efficient parallel information processing and low energy consumption. MXene-Ti3C2Tx, an emerging two-dimensional material, stands out as an ideal candidate for fabricating neuromorphic devices. Its exceptional electrical performance and robust mechanical properties make it an ideal choice for this purpose. This review aims to uncover the advantages and properties of MXene-Ti3C2Tx in neuromorphic devices and to promote its further development. Firstly, we categorize several core physical mechanisms present in MXene-Ti3C2Tx neuromorphic devices and summarize in detail the reasons for their formation. Then, this work systematically summarizes and classifies advanced techniques for the three main optimization pathways of MXene-Ti3C2Tx, such as doping engineering, interface engineering, and structural engineering. Significantly, this work highlights innovative applications of MXene-Ti3C2Tx neuromorphic devices in cutting-edge computing paradigms, particularly near-sensor computing and in-sensor computing. Finally, this review carefully compiles a table that integrates almost all research results involving MXene-Ti3C2Tx neuromorphic devices and discusses the challenges, development prospects, and feasibility of MXene-Ti3C2Tx-based neuromorphic devices in practical applications, aiming to lay a solid theoretical foundation and provide technical support for further exploration and application of MXene-Ti3C2Tx in the field of neuromorphic devices.
China Foundry•2025•DOI: 10.1007/s41230-025-4031-3
Columnar to equiaxial crystal transition (CET) is an important technological feature in many casting processes. This work investigated the CET during the solidification of Mg-Gd-Zn alloys by combining synchrotron radiation in-situ imaging and phase-field method. Results show that the grain size, dendrite tip radius, and secondary dendrite arm spacing (SDAS) all exponentially decrease with an increase in cooling rate (Vc). The variation in the radius of the dendritic tip is similar to the prediction of the Hunt model, while the variation in the SDAS is close to the Bouchard-Kirkaldy model. It is worth noting that the CET is promoted by a decrease in the temperature gradient (G) and an increase in the cooling rate (Vc). In both equiaxed and columnar crystal regions, the dendrite tip growth rate and solid phase volume fraction increase with increasing G and Vc. In addition, the CET process has been predicted by simulation. The results are consistent with the predictions of the GTK model, which is important for the in-depth study of the dendrite morphology in different crystallization regions. In the final stage, the effects of different critical subcooling degrees and nucleation densities on the CET were explored. The results show that increasing the critical nucleation supercooling degree can inhibit the generation of equiaxial crystals, while increasing the nucleation density helps to promote the CET.
Nano-Micro Letters•2025•DOI: 10.1007/s40820-025-01655-x
The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells (PSCs). However, serious ion migration hampers their operational stability. Although dopants composed of varied cations and anions are introduced into perovskite to suppress ion migration, the impact of cations or anions is not individually explored, which hinders the evaluation of different cations and further application of doping strategy. Here we report that a special group of sulfonic anions (like CF3SO3−) successfully introduce alkaline earth ions (like Ca2+) into perovskite lattice compared to its halide counterparts. Furthermore, with effective crystallization regulation and defect passivation of sulfonic anions, perovskite with Ca(CF3SO3)2 shows reduced PbI2 residue and metallic Pb0 defects; thereby, corresponding PSCs show an enhanced PCE of 24.95%. Finally by comparing the properties of perovskite with Ca(CF3SO3)2 and FACF3SO3, we found that doped Ca2+ significantly suppressed halide migration with an activation energy of 1.246 eV which accounts for the improved operational stability of Ca(CF3SO3)2-doped PSCs, while no obvious impact of Ca2+ on trap density is observed. Combining the benefits of cations and anions, this study presents an effective method to decouple the effects of cations and anions and fabricate efficient and stable PSCs.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2025-6-1)
Recent research progress on the use of Ni-based catalysts supported by various carbon materials, such as carbon nanotubes, graphene, and activated carbon, for the hydrogenation of CO2 to CH4 is summarized. The influence of additives and surface modification methods on improving their catalytic performance is discussed as is the reaction mechanism, especially the structure-function relationship produced by the carbon. The review provides a comprehensive directory for the rational design of carbon-supported Ni-based catalysts for the methanation of CO2.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2025-4-4)
The development of sustainable electrode materials for energy storage systems has become very important and porous carbons derived from biomass have become an important candidate because of their tunable pore structure, environmental friendliness, and cost-effectiveness. Recent advances in controlling the pore structure of these carbons and its relationship between to is energy storage performance are discussed, emphasizing the critical role of a balanced distribution of micropores, mesopores and macropores in determining electrochemical behavior. Particular attention is given to how the intrinsic components of biomass precursors (lignin, cellulose, and hemicellulose) influence pore formation during carbonization. Carbonization and activation strategies to precisely control the pore structure are introduced. Finally, key challenges in the industrial production of these carbons are outlined, and future research directions are proposed. These include the establishment of a database of biomass intrinsic structures and machine learning-assisted pore structure engineering, aimed at providing guidance for the design of high-performance carbon materials for next-generation energy storage devices.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-06-09)
During the operation of electronic devices, a considerable amount of heat and electromagnetic radiation is emitted. Therefore, the investigation of materials with electromagnetic shielding and thermal management abilities has significant importance. Hybrid materials of three-dimensional graphene networks containing both carbon nanotubes (CNTs) and SiC whiskers (3D graphene-CNT-SiC) were synthesized. Using an aqueous-phase reduction method for the self-assembly of the graphene oxide, a three-dimensional porous graphene structure was fabricated. SiC whiskers, inserted between the graphene layers, formed a framework for longitudinal thermal conduction, while CNTs attached to the SiC surface, created a dendritic structure that increased the bonding between the SiC whiskers and graphene, improving dielectric loss and thermal conductivity. It was found that the thermal conductivity of the hybrid material reached 123 W·m–1·K–1, with a shielding effectiveness of 29.3 dB when the SiC addition was 2%. This result indicates that 3D graphene-CNT-SiC has excellent thermal conductivity and electromagnetic shielding performance.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-06-03)
Petroleum asphalt, an important by-product of the petrochemical industry, has diverse applications but often suffers from low industrial added value. Because of its low cost, high carbon content, and high polycyclic aromatic hydrocarbon content, appropriate modification can increase its value and expand its energy storage applications. Current research progress on the common preparation methods of petroleum asphalt-based carbon materials, including template-assisted pyrolysis, molten salt treatment, activation, heteroatom doping, and pre-oxidation is reviewed, and its use in supercapacitors and alkali metal ion batteries, is also elaborated. Feasible solutions for the current problems with petroleum asphalt are proposed, with the aim of providing insights into its high value-added utilization.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-06-01)
The quest for sustainable energy storage solutions is more critical than ever, with the rise in global energy demand and the urgency of transition from fossil fuels to renewable sources. Carbon nanotubes (CNTs), with their exceptional electrical conductivity and structural integrity, are at the forefront of this endeavor, offering promising ways for the advance of electrochemical energy storage (EES) devices. This review provides an analysis of the synthesis, properties, and applications of CNTs in the context of EES. We explore the evolution of CNT synthesis methods, including arc discharge, laser ablation, and chemical vapor deposition, and highlight the recent developments in metal-organic framework-derived CNTs and a novel CNT aggregate with a three-dimensional ordered macroporous structure. We also examine the role of CNTs in improving the performance of various EES devices such as lithium-ion, lithium-metal, lithium-sulfur, sodium, and flexible batteries as well as supercapacitors. We underscore the challenges that remain, including the scalability of CNT synthesis and the integration of CNTs in electrode materials, and propose potential solutions and future research directions. The review presents a forward-looking perspective on the pivotal role of CNTs in shaping the future of sustainable EES technologies.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2024-39-02-13)
The oxidation reaction mechanism and its kinetics for ethylene tar were investigated in order to obtain a suitable anode material for Li-ion batteries. The oxidation of ethylene tar was divided into 3 stages (350–550, 550–700 and 700–900 K) according to the thermogravimetric curve. To reveal the oxidation reaction mechanism, the components of the gases evolved at different stages were analyzed by mass spectrometry and infrared technology. Based on these results the reaction was divided into 4 stages (323–400, 400–605, 605–750 and 750–860 K) to perform simulation calculations of the kinetics. Using the iso-conversion method (Coats-Redfern) to analyze the linear regression rates (R2) between 17 common reaction kinetics models and experimental data, an optimum reaction kinetics model for expressing the oxidation of ethylene tar was determined and the results were as follows. (1) During oxidation, the side chains of aromatic compounds first react with oxygen to form alcohols and aldehydes, leaving peroxy-radicals on aromatic rings. Subsequently, the aromatic compounds with peroxy-radicals undergo polymerization/condensation reactions to form larger molecules. (2) A fourth-order reaction model was used to describe the first 3 stages in the oxidation process, and the activation energies are 47.33, 18.69 and 9.00 kJ·mol−1 at 323–400, 400–605, 605–750 K, respectively. A three-dimensional diffusion model was applied to the fourth stage of the oxidation process, and the activation energy is 88.37 kJ·mol−1 at 750–860 K. A high softening point pitch was also produced for use as a coating of the graphite anode, and after it had been applied the capacity retention after 300 cycles increased from 51.54% to 79.07%.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2026-41-02-07)
Aqueous zinc-ion capacitors (ZICs) have significant potential as energy storage systems because of their high specific capacity and superior reliability. Heteroatom-doped carbon materials were known to substantially increase the capacitance of ZICs, however the mechanism remains poorly understood. Coal-based activated carbon was functionalized with B and N to serve as the cathode material in ZICs. This modification gave the material a high specific capacity of 371.4 mAh g−1 at 1 A g−1 and it retained 74% of its initial capacity after 10 000 cycles. Experimental results and density functional theory calculations revealed that pyridinic N plays a crucial role in increasing Zn2+ storage, demonstrating superior electrochemical reversibility. This work gives valuable insight into the design of high-capacity and ultrafast pseudocapacitive carbon cathodes for ZICs.
New Carbon Materials (新型炭材料)•2025•DOI: 10.1016/S1872-5805(NCM2025-40-01-04)
The ever-increasing integration of electronic devices has inevitably caused electromagnetic interference and heat accumulation problems, and dual-function materials with both a high thermal conductivity and high electromagnetic wave absorption (EWA) are regarded as an effective strategy for solving these problems. Carbon materials are widely used as thermal and EWA fillers due to their excellent conductivity and outstanding thermal conduction properties, and have become a research hotspot in the field of high thermal conductivity, microwave absorbing materials in recent years. The status of current research progress on carbon-based high thermal-conduction microwave absorption materials, including carbon fibers, carbon nanotubes, graphene and amorphous carbon, is reviewed, and the influence of the structure of the materials on their absorption and thermal conductivity properties, such as core-shell structure, three-dimensional network structure, and heteroatom doping, is also elaborated. Feasible solutions for the current problems with these materials are proposed, with the aim of providing valuable guidance for the future design of carbon-based high thermal conduction microwave absorbing materials.
Transactions of Nonferrous Metals Society of China (中国有色金属学报)•2025•DOI: 10.1016/S1003-6326(25)67012-9
The electrochemical separation of Mn(II) impurity from molten NaCl−KCl−MgCl2 was systematically investigated to facilitate the electrolytic production of high-purity magnesium. The reduction of Mn(II) to Mn metal on tungsten electrode was a quasi-reversible process controlled by diffusion. The apparent standard potential and exchange current density of Mn(II)/Mn(0) electrode reaction were determined at temperatures ranging from 973 to 1048 K. Solid Mn metal generated during electrolysis aggregated into irregular clumps and adsorbed some needle-like MgO, imposing a detrimental effect on both the aggregation and the purity of magnesium metal. After electrolysis at −1.5 V in molten NaCl−KCl−MgCl2−0.62wt.%MnCl2 for 8 h, the concentration of MnCl2 impurity decreased to 0.037 wt.%, achieving a removal efficiency of 94.14%. When direct electrolysis was performed in molten NaCl−KCl−MgCl2−0.62wt.%MnCl2, the obtained magnesium metal was small blocks with a caviar-like appearance, and the purity was just 98.59%. In contrast, a large globule of magnesium metal was obtained when electrolysis was performed in the purified electrolyte, and its purity was improved to 99.94%. The controlled-potential electrolysis proposed in this work has been verified to be a green and practically effective method to separate the metal ion impurities from molten electrolyte for high purity magnesium extraction.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.07.009
As the main geomaterials for coral reefs oil or gas extraction and underground infrastructure construction, coral reef limestone demonstrates significantly distinct mechanical responses compared to terrigenous rocks. To investigate the mechanical behaviour of coral reef limestone under the coupling impact of size and strain rate, the uniaxial compression tests were conducted on reef limestone samples with length-to-diameter (L/D) ratio ranging from 0.5 to 2.0 at strain rate ranging from 10−5 s−1 to 10−2 s−1. It is revealed that the uniaxial compressive strength (UCS) and residual compressive strength (RCS) of coral reef limestone exhibits a decreasing trend with L/D ratio increasing. The dynamic increase factor (DIF) of UCS is linearly correlated with the logarithm of strain rate, while increasing the L/D ratio further enhances the DIF. The elastic modulus increases with strain rate or L/D ratio increasing, whereas the Poisson’s ratio approximates to a constant value of 0.24. The failure strain increases with strain rate increasing or L/D ratio decreasing, while the increase in L/D ratio will inhibit the enhancing effect of the strain rate. The high porosity and low mineral strength are the primary factors contributing to a high RCS of 16.7%–64.9% of UCS, a lower brittleness index and multiple irregular fracture planes. The failure pattern of coral reef limestone transits from the shear-dominated to the splitting-dominated failure with strain rate increasing or L/D ratio decreasing, which is mainly governed by the constrained zones induced by end friction and the strain rate-dependent crack propagation. Moreover, a predictive formula incorporating coupling effect of size and strain rate for the UCS of reef limestone was established and verified to effectively capture the trend of UCS.
Int. Journal of Mining Science and Technology (采矿与安全工程)•2025•DOI: 10.1016/j.ijmst.2025.12.017
Given the high porosity, strong connectivity, and low strength of reef limestone, microbial-induced carbonate precipitation (MICP) reinforcement tests were performed under different grouting cycles. CT-based three-dimensional reconstruction, uniaxial compression, and acoustic emission analyses were employed to elucidate the coupling mechanism between microstructural evolution and macroscopic mechanical behavior. MICP-induced calcium carbonate deposition exhibited distinct scale selectivity, initially occurring in large pores and highly coordinated nodes, which reduced the average pore diameter from 221.26 μm to 75.36 μm and transformed the pore network from a highly connected loose type to a dense isolated one. The elastic modulus increased from 3.27 GPa to 6.21 GPa, and the peak strength approximately doubled, while the failure mode evolved from brittle to brittle–ductile. Acoustic emission analysis revealed a greater proportion of post-peak high-energy events and a frequency shift from high to mid–low ranges, indicating a multi-stage energy dissipation process. A reinforcement variable was introduced to quantify the MICP-induced strengthening, and a structural densification factor was incorporated to establish a constitutive model governed by densification. The study clarifies the coupling mechanism from microscopic densification to macroscopic enhancement, providing theoretical support for the green reinforcement of highly porous rock masses.
China Foundry•2025•DOI: 10.1007/s41230-025-3113-6
Annealing treatment is an effective strategy to enhance the comprehensive properties of Mg-8Li-3Al-2Zn (LAZ832) alloy, where the cooling rate plays a decisive role in tailoring microstructure and performance. This study systematically investigates the effects of cooling rates, controlled via water quenching (WC), air cooling (AC), and furnace cooling (FC), on the phase evolution, mechanical properties, and corrosion resistance of LAZ832. The annealed microstructure consists of α-Mg, β-Li, AlLi, and MgLi2Al phases, and the volume fraction of Al-Li phases (AlLi and MgLi2Al) increases as the cooling rate decreases. Strengthening mechanisms are dominated by solid solution strengthening, driven by the dissolution of Al and Zn atoms into the matrix, which significantly enhances tensile strength. However, excessive solute content leads to a marked decline in ductility. Scanning probe microscope (SPM) reveals an elevated work function due to the dissolution of Al and Zn atoms into the matrix phase, correlating with improved corrosion resistance. Comprehensive analysis demonstrates that air cooling achieves an optimal balance between tensile strength, ductility, and corrosion resistance, outperforming furnace-cooled samples and offering a pragmatic compromise compared to water-quenched specimens with higher strength but brittle failure. These findings establish a robust framework for designing LAZ832 alloys with tailored microstructures and multi-property optimization, advancing their application in lightweight engineering fields.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01232-8
Four-Wheel Independent Steering (4WIS) Vehicles can independently control the angle of each wheel, demonstrating superior trajectory tracking performance under normal conditions. However, on intermittent icy and snowy roads, the presence of time-varying adhesion coefficients, time-varying cornering stiffness, and the irregularities due to ice and snow accumulation introduce multiple uncertainties into the steering system, significantly degrading the trajectory tracking performance of 4WIS vehicles. In response, this paper proposes a robust Tube Model Predictive Control (Tube-MPC) trajectory tracking control method for 4WIS. In this method, a Bi-directional Long Short-Term Memory neural network is established for online estimation of tire cornering stiffness under different road adhesion coefficients, providing accurate estimation of time-varying cornering stiffness for each wheel to mitigate the uncertainties of time-varying adhesion coefficients and cornering stiffness. Additionally, considering the road irregularities caused by snow accumulation on intermittent icy and snowy roads, a trajectory tracking controller that integrates Tube-MPC and robust Sliding Mode Control is proposed. The nominal MPC model, developed from the estimated tire cornering stiffness, utilizes the sliding surface and the optimal auxiliary control unit law for the tube is derived from the reaching law in Tube-MPC, aiming to minimize the trajectory tracking error while enhancing the controller’s robustness against road uncertainties. The experiments show that the proposed method outperforms the Tube-MPC algorithm in terms of trajectory accuracy and robustness. This method demonstrates excellent trajectory tracking accuracy under intermittent icy and snowy road conditions, and it lays a theoretical foundation for future studies on vehicle stability and trajectory tracking under such road conditions.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3080-8
Hydrogen displays the potential to partially replace pulverized coal injection (PCI) in the blast furnace, and it can reduce CO2 emissions. In this paper, a three-dimensional mathematical model of hydrogen and pulverized coal co-injection in blast furnace tuyere was established through numerical simulation, and the effect of hydrogen injection and oxygen enrichment interaction on pulverized coal combustion and raceway smelting was investigated. The simulation results indicate that when the coal injection rate decreased from 36 to 30 t/h and the hydrogen injection increased from 0 to 3600 m3/h, the CO2 emissions decreased from 1860 to 1551 kg/t, which represents a 16.6% reduction, and the pulverized coal burnout decreased from 70.1% to 63.7%. The heat released from hydrogen combustion can not only promote the volatilization of pulverized coal but also affect the combustion reaction between volatilization and oxygen, which resulted in a decrease in the temperature at the end of the raceway. Co-injection of hydrogen with PCI increased the wall temperature near the upper half part of the raceway and at the outlet of the tuyere, which required a high cooling efficiency to extend the service life of the blast furnace. The increase in oxygen level compensated for the decreased average temperature in the raceway due to hydrogen injection. The increase in the oxygen content by 3% while maintaining constant hydrogen and PCI injection rates increased the burnout and average raceway temperature by 4.2% and 43 K, respectively. The mole fraction of CO and H2 production increased by 0.04 and 0.02, respectively. Burnout can be improved through optimization of the particle size distribution of pulverized coal.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01308-5
Aircraft have received much attention because of their capability to adapt to various flight environments and complex missions. The nose cone is one of the key elements in optimising the aerodynamic shape of aircraft. A morphing nose cone (MNC) driven by a biomimetic 4-3R1U&3R parallel mechanism is proposed in this study. Based on screw theory, the parallel mechanism’s configuration is determined, and the structure’s full-cycle degrees of freedom are concurrently confirmed. Examples in the paper demonstrate the viability of the structure by configuration synthesis, and diagrams also show the chains. This MNC is modelled after the structural design of the cicada’s abdomen and can be extended, contracted and bent. It can actively adjust its shape in response to change in the flight environments, thereby aerodynamic performance and enhancing the aircraft’s multi-mission capabilities. A scaled-down prototype is created to verify the deformation capacity of the MNC meeting the engineering requirements. Results show that the extension ratio is 36.7%, and the bending angle is 21.7°, which is better than expected. The relative error value is within a reasonable range and the extension process is incredibly stable. This research proposes new perspectives for the design of MNCs.
Chinese Journal of Mechanical Engineering•2025•DOI: 10.1186/s10033-025-01337-0
Origami mechanisms are extensively employed in various engineering applications due to their exceptional folding performance and deformability. The key to designing origami mechanisms lies in the design of the creases. The crease design is often derived from experience and inspiration, so it is crucial to have a systematic approach to crease design. In this paper, a novel synthesis approach based on graph theory is proposed, which effectively addresses the challenge of designing the creases in origami mechanisms. The essence of this method lies in the acquisition of the double symmetrical crease pattern through the directed graph product operation of two subgraphs. The crease pattern can be simplified by employing a technique that eliminates certain creases while preserving the non-isomorphism and symmetry of the pattern. An improved mixed-integer linear programming model is developed to achieve an automatic distribution of the peak_valley creases of the origami. The proposed method ultimately generates 12 unique double symmetrical crease patterns. The new method proposed in this paper, through systematic design, significantly improves the efficiency of mechanism design while opening up broad prospects for exploring new mechanism structures, thereby greatly expanding its application potential in cutting-edge fields such as aerospace engineering and intelligent robots.
Journal of Central South University•2025•DOI: 10.1007/s11771-025-6106-0
Iron removal from zinc leachate in hydrometallurgy produces large volumes of low-grade, impurity-laden iron waste, posing significant environmental challenges. Magnetite precipitation offers a novel method for iron removal and resource recycling in zinc hydrometallurgy. However, the chemical similarity between ferrous and zinc ions, along with high zinc concentrations, causes zinc co-precipitation, challenging its application. To address this issue, this study utilized electron microscopy to observe key intermediate products in magnetite crystallization and employed EXAFS (extended X-ray absorption fine structure) to analyze their evolutionary mechanisms and zinc-binding configurations. The results indicate that the intermediate products during magnetite formation are sequentially green rust, feroxyhyte (δ-FeOOH), and weakly crystalline nanoparticles, and further analysis revealed that their transformation follows the dissolution-recrystallization mechanism. Furthermore, it was found that intermediate products such as green rust exhibit strong binding with zinc (via adsorption and lattice substitution), which was confirmed as a significant reason for the difficulty in separating zinc from magnetite. This study elucidates the transformation process of intermediate products during magnetite formation and, for the first time, reveals the binding configurations of zinc with these key intermediate products. This has significant implications for the development and optimization of new technologies for the efficient separation of iron and zinc during the magnetite precipitation process.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3075-5
An effective approach to enhance the surface degradation characteristics of laser powder bed fusion (LPBF) type 420 stainless steel involves the incorporation of spherical cast WC/W2C to create LPBF metal matrix composites (MMCs). However, the corrosion behavior of stainless steel and cast WC/W2C varies inversely across different pH levels, and the phenomenon of pitting corrosion in LPBF MMCs under varying pH conditions remains insufficiently explored. In LPBF 420 + 5wt% WC/W2C MMCs, pits form adjacent to cast WC/W2C in acidic and neutral environments, attributed to the presence of chromium-rich carbides and galvanic coupling effects. The dissolution of the reinforced particles facilitates pit nucleation in alkaline conditions. Notably, in-situ reaction layers exhibit superior corrosion resistance to the matrix or the reinforced particles across all pH levels. The distinct corrosion mechanisms influence the pitting corrosion behavior, with the corrosion ranking based on critical pitting potential being neutral > alkaline > acidic, contrasting the observed kinetics of pit growth (alkaline > acidic > neutral).
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3257-9
A series of as-cast SixAl0.43CoCrFeNi2.1 (x = 0, 0.1, 0.2, and 0.3) high-entropy alloys (HEAs) was successfully fabricated by vacuum-assisted melting. The phase constituents, microstructural features, and mechanical properties (including hardness, tensile behavior, and wear behavior) of alloys with various Si contents were evaluated. The results revealed that the addition of Si promoted the precipitation of a body-centered cubic 1 (BCC1) phase enriched in Al, Ni, and Si with a B2-ordered structure. Furthermore, the secondary BCC2 phase was enriched with Cr, Fe, and Si precipitates within the BCC1 matrix. Ultimately, a multiphase face-centered cubic (FCC)/(BCC1/BCC2) structure was formed. The microstructural evolution driven by Si addition significantly enhanced the mechanical properties of the SixAl0.43CoCrFeNi2.1 HEAs. As the Si content increased, the microhardness and tensile strength improved by approximately 42% and 55%, reaching 2.359 GPa and 785 MPa, respectively. The quantitative evaluation of the various strengthening mechanisms indicated that the intrinsic hardness of the FCC matrix and hardening due to BCC1/BCC2 precipitation dominated the overall microhardness. The comparison of the energy barriers indicates that BCC2 primarily strengthens the alloy through a shear mechanism rather than an Orowan bypass mechanism. Furthermore, with increasing Si content, reduced friction and wear, together with smoother worn surfaces, reflect a greatly enhanced wear resistance. After the optimal cold-rolling and 1 h annealing at 800°C, the Si0.3Al0.43CoCrFeNi2.1 alloy showed 56% and 62% increases in microhardness and tensile strength, respectively, compared to the as-cast state, reaching 3.68 GPa and 1270 MPa. The enhanced mechanical properties are attributed to the synergistic effects of residual strain hardening by FCC ordering and L12/BCC precipitation strengthening.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-025-3096-8
Red mud is a kind of industrial waste residue produced in the process of alumina production, which has strong suspension and is difficult to precipitate and filter. This study compared the effects of 4 kinds of filter aids, including CaCl2, polymerized ferrous sulfate (PFS), steel slag (SS), and Portland cement (PC), on the filtration rate, filter cake moisture content, and Na2O content of red mud slurry. At a dosage of 10 g·L‒1, the filtration effects were in the following order: PFS > CaCl2 > SS > PC. Under the combination of 5 g·L‒1 SS and 5 g·L‒1 PC, the better filtration effect was achieved with a filtration time of 205.17 s, which was reduced by 58.52% compared to the original red mud. The combined use of SS and PC exhibits better advantages in terms of cost and filtration effect. This study provides a data foundation for the rapid filtration of red mud slurry. The use of SS and PC as filter aids for red mud holds broad application prospects.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3076-4
CoFe bimetallic hydroxides (CoFe BMHs) find wide applications as excellent catalysts in the field of water splitting. However, no study has systematically investigated the influence of the morphologies of CoFe BMHs on catalyst performance. In this study, CoFe BMH nanoflowers (CoFe BMH NFs), CoFe BMH nanosheets (CoFe BMH NSHs), CoFe BMH nanorods (CoFe BMH NRs), and CoFe BMH nanospheres (CoFe BMH NSPs) were prepared on nickel foam via a hydrothermal method. CoFe BMH NSHs exhibited the most beneficial catalytic activity. At a current density of 100 mA·cm−2, its overpotential for oxygen evolution reaction (OER) was 282 mV, and the overall water splitting voltage was 2.05 V. The double-layer charging capacitance (Cdl) value of CoFe BMH NSHs was the largest in CoFe BMHs, which proves that CoFe BMH NSHs have the largest active area. Furthermore, the active site in the OER process was metal oxyhydroxide (MOOH) through in situ Raman characterization, and the generation of the active substance was an irreversible process. This work provides important insights into the design of catalyst morphologies and offers valuable guidelines for the enhancement of the performance of other catalysts.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3084-4
The effect of cryogenic treatment (CT) and relaxation annealing on the average nearest neighboring distance of atom (dm), thermodynamic stability, soft magnetic properties, microhardness (Hv), and corrosion resistance of as-spun (Fe0.5Co0.5)75B21Nb4 metallic glasses (MGs) is studied. On the premise of maintaining a fully amorphous phase, appropriate CT and relaxation annealing are conducive to achieving the synergistic effect of increasing saturation magnetization (Ms) and reducing coercivity (Hc). Shallow CT at 213 K optimally enhances the soft magnetic properties of MGs. Given its low activation energy of nucleation and increased activation energy of growth, appropriate CT is beneficial for achieving uniform annealed nanocrystals in amorphous phases. The correlation between free volumes (FVs) and potential energy suggests that the variation in Hc depends on the expansion and contraction behavior of amorphous phases after different CT processes. The fitting formulas of Hc–dm and Ms–Hv correlations demonstrate that soft magnetic parameters have a solid linear relationship with the contents of FVs and degree of dense random packing. Moreover, pitting resistance is improved by appropriate CT and relaxation annealing. This improvement is characterized by the promotion of the stability of the Nb-rich passive film formed during electrochemical corrosion in 3.5wt% NaCl solution.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2988-3
The <001> orientation of the Goss texture aligned with the rolling direction is the most easily magnetized direction, effectively enhancing the magnetic properties of non-oriented silicon steel. In the present study, an ultra-thin high-silicon sheet of 0.2 mm with a strong Goss texture was successfully fabricated using a two-stage rolling method, achieving superior magnetic properties. The combination of suitable primary rolling reduction and intermediate annealing proved beneficial in promoting the formation of Goss texture. Electron back scatter diffraction (EBSD) was used to characterize micro-shear bands within deformed grains of secondary rolled sheets. Observations revealed that the recrystallized Goss nucleus originated from the Goss substructure of shear bands within deformed {111}<112> grains during the initial stages of recrystallization. The influence of stored energy and grain size on texture evolution was thoroughly investigated using quasi-in situ EBSD during recrystallization. In the initial stages, large deformed {111}<112> and near {111}<112> grains with high stored energy facilitated nucleation and growth of Goss and near-Goss grains within shear bands and reduced grain boundary nucleation. In the later stages, large deformed grains with low stored energy underwent a strain-induced grain boundary migration mechanism to nucleate. During the recrystallization, many recrystallized Goss and near-Goss grains clustered together, with Goss grains rotating towards near-Goss orientation. The resulting annealed ultra-thin 0.2 mm sheet with a pronounced Goss texture exhibited superior magnetic properties.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-2993-6
Hypoeutectoid steel, a crucial metal structural material, is characterized by the coexisting microstructure of ferrite and pearlite. Driven by multiphase competition and multicomponent characteristics, the intricate interplay among its composition, processing conditions, and microstructure substantially complicates the understanding of austenite decomposition kinetics and elemental diffusion mechanisms during phase transformations. The present study explores the effects of cooling rate, prior austenite grain size, and C content on the component distribution and microstructure evolution during the austenite decomposition of hypoeutectoid steels to address the aforementioned complexities. Results of a multiphase field model reveal that an increase in the cooling rate from 1.0 to 7.0°C/s leads to a reduction in the ferrite proportion and fine pearlite lamellae spacing from 52vol% to 22vol% at 400°C and from 1.01 to 0.67 μm at 660°C, respectively. Concurrently, a decreased prior austenite grain size from 25.23 to 8.92 μm enhances the phase transformation driving force, resulting in small average grain sizes of pearlite clusters and proeutectoid ferrite. Moreover, increasing the C content from 0.22wt% to 0.37wt% decreases the phase transition temperature from 795 to 750°C and enhances the proportion of pearlite phases from 27vol% to 61vol% at 500°C, concurrently refining the spacing of pearlite layers from 1.25 to 0.87 μm at 600°C. Overall, this work aims to elucidate the complex dynamics governing the microstructural transformations of hypoeutectoid steels, thereby facilitating their wide application across different industrial scenes.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3053-y
Hydrogen-based mineral phase transformation (HMPT) technology has demonstrated its effectiveness in separating iron and enriching rare earths from Bayan Obo refractory ores. However, further research is needed to clarify the phase composition and floatability of rare earths obtained after HMPT owing to the associated phase transformations. This study explored the mineralogical characteristics and separation behavior of rare earths in HMPT-treated iron tailings. Process mineralogy studies conducted via BGRIMM process mineralogy analysis and X-ray diffraction revealed that the main valuable minerals in the tailings included rare-earth oxides (9.15wt%), monazite (5.31wt%), and fluorite (23.52wt%). The study also examined the impact of mineral liberation and gangue mineral intergrowth on flotation performance. Flotation tests achieved a rare-earth oxide (REO) grade of 74.12wt% with a recovery of 34.17% in open-circuit flotation, whereas closed-circuit flotation resulted in a REO grade of 60.27wt% with a recovery of 73%. Transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive spectroscopy revealed that monazite remained stable during the HMPT process, while bastnaesite was transformed into Ce7O12 and CeF3, leading to increased collector consumption. Nonetheless, the HMPT process did not significantly affect the flotation performance of rare earths. The enrichment of fluorite in the tailings highlighted its further recovery potential. The integration of HMPT with magnetic separation and flotation presents an efficient strategy for recovering rare earths, iron, and fluorite from Bayan Obo ores.
Int. Journal of Minerals, Metallurgy and Materials (矿物冶金与材料学报)•2025•DOI: 10.1007/s12613-024-3007-4
The enrichment of chromium in the magnetic iron chromite (Fe(CrxFe1−x)2O4) phase is crucial for the recovery and recycling of chromium in stainless-steel pickling sludge. The kinetics and reaction mechanism of the solid-phase reaction between Fe3O4 and Cr2O3 were investigated using the diffusion couple method at 1473 K. Not only the diffusion behavior of Fe2+ ions and Cr3+ ions was elucidated, but also the solid solution behavior of Fe3+ ions was discussed clearly. The microscopic morphology of the diffusion couple and the change in the concentrations of Fe and Cr cations across the diffusion layers were analyzed using scanning electron microscopy and energy dispersive spectroscopy. The self-diffusion coefficients of cations were calculated based on the concentration profiles of Fe and Cr, with the results indicating that the self-diffusion coefficient of the Fe ions was consistently higher than that of the Cr ions. Additionally, a mixture of Fe3O4 and Cr2O3 was annealed at 1373–1473 K for 1–5 h, and the kinetic parameters were calculated by studying the phase content of the product. The phase content of Fe(CrxFe1−x)2O4 in the product was determined by Rietveld refinement of X-ray diffraction data, revealing that an activation energy (E) of 177.20 kJ·mol−1 and a pre-exponential factor (B) of 610.78 min−1 of the solid-phase reaction that produced the Fe(CrxFe1−x)2O4 spinel.
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.