- Ei，ESCI收录期刊
- 中国科学引文数据库(CSCD)核心期刊
- 中文核心期刊
- 文摘与引文数据库(Scopus)
- 剑桥科学文摘(CSA)
The electromagnetic environment has been increasingly complicated， requiring more effective electromagnetic protection. However traditional absorbents possess a single absorption mechanism which is unable to achieve comprehensive excellent performance. Therefore， it is necessary to integrate multiple types of absorbents to enrich the mechanisms responsible for electromagnetic wave loss. Moreover， the microstructures of absorbents are designed to enhance their impedance matching and loss attenuation performance. These approaches can facilitate multiple reflections and scattering of incident electromagnetic waves. In this work， the progress of researches on absorbent microstructure design and its performance control are comprehensively reviewed， both domestically and internationally. Then the influence of microstructure design on absorbent loss mechanisms， optimal reflection loss coefficients， and effective absorption bandwidths are analyzed. Finally， the exploration of absorbents loss mechanism， research methods of system screening and microstructure design， as well as the future development of multifunctional absorbent materials are summarized and prospected.
Metamaterials have garnered significant attention in the field of electromagnetic wave absorption due to their unique electromagnetic absorption properties. However， conventional metamaterial absorbers， with their fixed structures and materials， struggle to meet the demand of dynamically controlling electromagnetic stealth for weapons and equipment in complex battlefield environments. By incorporating tunable units， the electromagnetic properties of metamaterial absorbers can be flexibly and dynamically controlled through external excitation sources. This capability plays a crucial role in enhancing the efficacy of electromagnetic stealth for weapons and equipment. In this paper， the mechanism of regulating the metamaterial electromagnetic performance is elucidated through equivalent circuit. The current research status of tunable metamaterial absorbers， which utilize active materials， dynamic structures and circuit components， is introduced in detail. To explore the application performance of tunable metamaterial absorbers， the existing bottleneck issues in current research， such as control range and response speed are also discussed. Furthermore， the future development direction is extensively explored from the aspects of intelligent perception control， adaptive adjustment optimization， networked collaborative control， and self-powered energy supply， providing a valuable reference for the continued advancement and application of tunable metamaterial absorbers.
Conductive polymer composites （CPCs） with positive temperature coefficient （PTC） have a wide range of applications in the field of smart heating due to the combination of good electrical conductivity of inorganic fillers and excellent processing properties of polymers. Among them， the percolation threshold， Curie temperature， PTC strength and PTC reproducibility are important parameters for the realization of the PTC effect. Therefore， based on the conductive mechanisms of CPCs and the generation mechanisms of PTC effect， this paper systematically reviews the regulation mechanisms of PTC effect from the perspective of both polymer matrix and filler， and proposes feasible strategies for lowering the percolation threshold， regulating the Curie temperature， improving the PTC strength， and enhancing the reproducibility of PTC， which provides guidance for the design and development of polymer matrix composites with PTC.
Ionogel is an electrolyte material consisting of ionic liquids （ILs） as dispersed phases fixed via organic or inorganic networks. It has received considerable attention in recent years due to its unique biphasic solid-liquid phase properties， excellent chemical， electrical and thermal stability， and extensive electrochemical windows. In particular， it has great potential for flexible electronic device construction， chemical composition detection and wearable sensing. This review mainly analyzes the structural characteristics and component properties of ionogels， discusses the effects of various materials on the modification and performance of ionogels， and describes the key application of ionogel flexible materials in the fields of personalized health monitoring， motion quality assessment， human-computer interaction， and marker detection. Finally， the future challenges and design strategies of flexible ionogel materials are proposed.
In recent years， the application demand of high-performance composites and the structural design of novel materials have exhibited synergistic advancement. Research on bionic structures has served as an innovative foundation for developing high-performance composite structural materials， while also providing efficient methodologies for designing new devices. Both antarctic penguin feathers and polar bear fur have natural macro-nano porous structures， which low thermal conductivity facilitates thermoregulation in extremely cold regions. Inspired by the exceptional thermal insulation performance of hollow structures， researchers have biomimetically designed and scalably fabricated a series of thermal insulation materials across multiple scales， accompanied by systematic investigations of their properties， thereby accelerating the engineering application of such materials. This review critically examines recent advancements in bionic hollow insulation materials， outlines prospective research directions for this class of materials， and investigates their potential applications in interfacial solar thermal evaporation， energy utilization， and ecological conservation. Through in-depth analysis of biological structural characteristics and comprehensive investigation of structure-property relationships in practical applications， this field is poised to advance the design and development of biomimetic materials with enhanced structural stability and superior performance.
With the increasing service time of pressurized water reactor nuclear power plants， the weldability of austenitic stainless steel， used as a core structural material in reactors， gradually deteriorates due to neutron irradiation damage. Neutron irradiation leads to the formation of microstructural defects such as voids， helium bubbles， and dislocation loops within the material， where helium is generated through nuclear transmutation reactions involving boron （B） and nickel （Ni）. During welding， helium diffuses and accumulates at grain boundaries， forming helium bubbles，and the tensile stress generated during post-weld cooling promotes the formation of helium induced cracks （HeIC）. This paper reviews the irradiation damage mechanisms of austenitic stainless steel after neutron irradiation， focusing on the formation mechanism and influencing factors of HeIC. The threshold helium concentration of HeIC under different welding methods is analyzed， highlighting a significant relationship between welding heat input and the threshold helium concentration. Reducing heat input can effectively increase the threshold concentration. Furthermore， this paper summarizes two main methods to suppress helium-induced cracking： reducing welding heat input and minimizing welding tensile stress， and introduces advanced welding techniques such as auxiliary beam stress improvement laser welding. Finally， this paper emphasizes the need to focus on developing high-energy-density welding equipment and intelligent welding control technologies to address the challenges of welding repair for reactor internal components in nuclear power plants.
The creep deformation mechanism of the superalloy at 760 ℃ is investigated by analyzing the creep deformation behavior of a third-generation nickel-based single crystal superalloy at 760 ℃ and characterizing its microstructural evolution and dislocation configurations. The results show that the primary creep deformation mechanism at 760 ℃ is the shearing of dislocations into the γ′ phase. In the initial creep stage， the predominant form of dislocation dissociation within the γ′ phase involves Shockley partial dislocations coupled with stacking faults. Stacking faults on different ｛111｝ planes can interact with each other， forming Lomer-Cottrell （L-C） dislocation locks. During the later creep stage， a large number of a〈011〉 superdislocations shear into the γ′ phase， and these superdislocations can cross-slip from ｛111｝ planes onto ｛001｝ planes， forming Kear-Wilsdorf （K-W） locks with non-planar structures. Throughout the creep process， the formation of both L-C locks and K-W locks impedes dislocation motion， thereby enhancing the creep resistance of the superalloy.
The microstructure evolution and tensile properties at room temperature of TA15 titanium alloys during heat treatment at different temperatures are investigated by optical microscopy （OM）， scanning electron microscopy （SEM）， and transmission electron microscopy （TEM）. In particular， the double fluctuation behavior of tensile strength at room temperature in TA15 titanium alloys after heat treatment in the ranges of 800-900 ℃ and above 950 ℃ are characterized and analyzed in detail. The results show that with the increase of the heat treatment temperature， the microstructure evolution of equiaxed α phase+lamellar secondary α phase and β phase→equiaxed α phase+lamellar secondary α phase and β phase （internal newly formed fine α phase and β phase laths）→coarsened newly formed α phase and β phase laths undergoes in TA15 titanium alloys， which results in the increase trend of tensile strength at room temperature of TA15 alloys. The newly formed α phase and β phase laths at relatively high temperatures during the heat treatment absorb stagewise secondary α phase laths and equiaxed primary α phase， followed by coarsening as the heat treatment temperature further increases. It is concluded that the strengthening effect of newly formed α phase and β phase laths leads to the strength increase in the range of 800-900 ℃. Within the 900-950 ℃ range， the newly formed lamellar α phase and β phase absorb the original lamellar secondary α+β phase， and the lamellar size in the newly formed α phase and β phase laths is relatively coarse， resulting in a slight decrease in strength. Above 950 ℃， the dissolution of the equiaxed α phase and its transformation into a higher proportion of newly formed α phase and lamellar β phase once again enhances the strengthening effect of the lamellar structure， causing a secondary peak in the tensile strength at room temperature above 950 ℃.
The correlation between ingot shrinkage and Al-rich defects is studied by prefabricated shrinkage， forging and stamping deformation. For Al-rich segregation defects in bars， the results show that the dark banding is presented at low magnification via visual observation， and the dense α phase characteristic is shown at high magnification via optical microscope. The content of α phase in the defect area is 88.26%， which is much higher than 47.23% in the normal area. Besides， there is obvious enrichment of aluminum element in the defect area， and the energy spectrum results show that the average content of Al element is as high as 9.58%（mass fraction， the same below）， which is significantly higher than 5.86% in the normal area. Moreover， the average microhardness is 401.33HV， which is higher than that of the normal region 304.33HV as well. For the ingot shrinkage， the results show that the enrichment of Al element is the most obvious in the top surface part of the shrinkage cavity. The average content is as high as 9.59% in the top surface of shrinkage cavity， but is only 5.33% in the bottom surface part. The enrichment of Al elements in shrinkage of ingot corresponds to the segregation of Al-rich defects in bars， indicating that the enrichment of Al element in the shrinkage cavity is hereditary.
Due to the introduction of particles between the electrode and the substrate during electrospark particle planting， there is a significant difference in its forming process compared to traditional electro-spark deposition processes. In this study， TiC particles are electrospark planted on the surface of a single crystal superalloy substrate under different pulse width parameters. By observing its surface morphology and cross-sectional morphology， analysing its microstructure， and conducting shear force experiments to explore its mechanical properties， the effects of different pulse widths on the microstructure and properties of spark discharge implanted particles are obtained. The research results indicate that during the process of spark discharge particle implantation， both the particles and the substrate melt and fuse together， resulting in metallurgical bonding between the particles and the substrate. The micropores on the surface of the particles are eliminated， while the internal pores are filled with metal. As the pulse width increases， the pulse energy of spark discharge particle implantation increases， the fusion zone of the particles increases， and the contact angle between the particles and the substrate decreases. Due to an increase in pulse width （such as a pulse width of 80%）， particles are broken and their shear force performance is reduced. Therefore， in this experiment， the shear performance of particles is optimal when the pulse width is 60%.
The microstructure of the Mg-5Al-0.2Ag alloy is modulated by sub-rapid solidification and subsequent cryogenic treatment， and the mechanism for improving mechanical properties of the alloy is studied. The results show that the microstructure of the Mg-5Al-0.2Ag alloy after sub-rapid solidification is almost single solid solution with grain size of 25 μm， and there are plenty of Al solute clusters and Al atoms dissolve in Mg matrix with a high solute content. Moreover， the compressive strength of the alloy after sub-rapid solidification increases by 26.6% compared to that of the alloy produced by conventional casting. After further cryogenic treatment of the Mg-5Al-0.2Ag alloy after sub-rapid solidification， the compressive strength and the compression strain of the alloy are as high as 493 MPa and 41.7% respectively. The simultaneous improvement of strength and plasticity can be attributed to two factors. On the one hand， the structure refinement occurs because the Mg matrix are cut apart by the motivated twins. On the other hand， dislocation motion is hindered by twin boundaries and the nano-precipitate.
An environmentally friendly conversion coating is prepared on AZ91D magnesium alloy surface by chemical conversion method using tannic acid as the coating forming agent to improve corrosion resistance. The acid regulating the pH value of the conversion solution is selected by contrast experiment. The pH value， reaction temperature， and conversion time are optimized by the Box-Behnken test， and the optimum process conditions are obtained. The effect of pH value on the corrosion resistance of the conversion coating is also discussed. CuSO4 pitting time and electrochemical experiments are used to judge the corrosion resistance， SEM and EDS are used to characterize the coating surface morphology and element composition of AZ91D magnesium alloy. The results show that the optimum process of tannic acid conversion coating is as follows： tannic acid content 10 g/L， pH value 2.7 （hydrochloric acid regulation）， reaction temperature 41 ℃， conversion time 15 min. The conversion coating has good corrosion resistance， uniform density， and the covering is complete. The coating is mainly composed of tannic acid hydrolysate and Mg2+ chelate. Box-Behnken test result shows that the pH value has a great influence on the corrosion resistance of the conversion coating. When the pH value is too low， the coating is rough and poorly compacted；while when the pH value is too high， the coating is thin and lacks continuity， which cannot completely cover the surface of the magnesium alloy.
The microstructure and mechanical properties of the samples located at the surface and core of the spray-quenched 2219-T6 aluminum alloy thick plate are studied. The results show that the second phase in the alloy consists of Al3（Cu， Fe， Mn） crystalline phase with a size of 0.5-30 μm， submicron sized θ-Al2Cu phase and T phase， as well as nano-level semi coherent precipitated θ′ and θ″ phases. During spray quenching， the surface of the plate cools faster， resulting in a higher density of the θ″ phase in that area. At room temperature， the tensile strength and yield strength of the surface layer are 427 MPa and 303 MPa， respectively， which are increased by 9.2% and 15.6% compared to that of the core layer. Meanwhile， the plasticity of the surface layer is lower than that in the core layer， which is related to the superior strengthening effect of the surface layer by the precipitation of the θ″ phase. The cracks in the samples propagate in a mixed mode of intergranular and transgranular propagation. Due to the lower relative slip resistance of dislocations precipitated in the core layer compared to the surface layer， dislocations are more likely to accumulate near large-sized crystalline phases and grain boundaries， leading to the formation of more secondary cracks in the sample during fracture process. In addition， the tensile fracture surfaces of the samples are mainly composed of ductile dimples， exhibiting obvious ductile fracture characteristics.
Cu/Al composites， which combine the advantages of high electrical conductivity of Cu and low density of Al， have been used in aerospace， electronics， and other important industrial fields， but there are difficulties in realizing the effective metallurgical connection between the two metals. In this study， the Cu/Al composites are obtained by depositing AlSi10Mg on T2 violet Cu substrate using laser directed energy deposition （L-DED） technique. The results show that the high residual stress and thick compound layer at the interface of the samples without preheating conditions lead to serious crack defects， while the interfacial cracks are successfully eliminated by preheating the substrate and dense metallurgical bonding is realized. Three kinds of Cu/Al intermetallic compounds， γ-Al4Cu9， η-AlCu and θ-Al2Cu， exist in the Cu/Al bonding region of the samples under preheating. According to the microstructure， the bonding region is divided into transition and remelting zones， the bottom of the transition region is the layered γ-phase and η-phase， and the upper part is mainly the incipient θ-phase and eutectic zone produced by Cu/Al over-eutectic， and the structural evolution is as follows： Cu→γ+（Si）→η→θ+（α-Al）+（Si）→θ+Si+（α-Al+θ）+（α-Al+Si）→θ+（α-Al+θ）+（α-Al+β-Si）+（α-Al+θ+β-Si）； fine α-Al isometric crystals， grain boundary mesh θ phase and incipient Si precipitation are formed in the remelting zone， and Si mainly forms incipient phases in the Cu/Al bonding region， and forms a eutectic organization with Al and Cu at the top of the transition zone. The microhardness of different regions of the preheated samples presents： transition zone > remelting zone > AlSi10Mg zone > Cu substrate.
QP1180 quenching-partitioning steel and 22MnB5 hot press forming（HPF） steel are two main lightweight materials for automobiles. QP1180 is a 1.2 GPa cold forming steel， while 22MnB5 is a 1.5 GPa HPF steel， which needs to undergo HPF to obtain high strength. These two materials are often used in automobile manufacturing and need to be connected. To investigate the properties of the welded joints of these two ultra-high strength steel plates， two approaches are employed： first， laser tailor welding of QP1180 and 22MnB5 followed by HPF quenching； and second， the steel of 22MnB5 is HPF quenching and then laser tailor welding. The differences in microstructure and mechanical properties of the laser tailor welded joints before and after HPF quenching are compared by using optical microscopy（OM）， scanning electron microscopy（SEM）， uniaxial tensile test and a Vickers hardness test. The results show that compared to joints made by HPF quenching first then laser tailor welding， joints made by laser tailor welding first then HPF quenching exhibit a 20.7% increase in tensile strength， 90.3% increase in elongation after fracture， and 140% increase in hardness. No softening occurs on either side of the welded joint， and the microstructure in the softening zone transforms from the original martensite+ferrite to fine martensite. The tensile strength， elongation after fracture， and hardness all increase compared to the pre-welding HPF quenched state. The enhancement of these properties can improve the formability and serviceability of the components.
The CoCrCuFeNiTi high entropy alloy cladding layers with 2%（mass fraction）CeO₂ and without CeO₂ are respectively prepared on the surface of Q550 steel by laser cladding technology. The phase composition， microstructure，and elemental distribution of the two cladding layers are analyzed by characterization methods such as XRD， SEM， and EDS. The microhardness， wear resistance and corrosion resistance of the cladding layers are tested by using a Vickers hardness tester， a friction and wear testing machine and an electrochemical workstation. The results show that the addition of CeO₂ does not change the FCC+BCC two-phase structure of the cladding layers， but it causes lattice distortion， resulting in the diffraction peaks moving towards a low angle. The addition of CeO₂ refines the grain size of the cladding layers and makes the element distribution more uniform. The average microhardness of the cladding layers increases from 451.94HV0.5 to 533.50HV0.5， the wear mass loss decreases from 0.0031 g to 0.0029 g， and the wear mechanism changes from adhesive wear to abrasive wear. After adding CeO₂， the corrosion current density of the cladding layers decreases from 9.336 μA·cm-2 to 2.137 μA·cm-2， the charge transfer resistance increases from 0.332×104 Ω·cm2 to 1.771×104 Ω·cm2， and the corrosion resistance is enhanced.
Element doping can alter the structure of the base material， thereby enhancing its performance. Undoped and Zr-doped Y2O3 films are deposited on single-crystal silicon and polycrystalline CVD diamond by magnetron sputtering to investigate the composition， structure， and properties of Zr-doped yttrium oxide （Y2O3） antireflection films. Grazing incidence X-ray diffraction （GI-XRD） results reveal that the undoped Y2O3 films exhibit a cubic （222） plane columnar crystal orientation. As the Zr doping power increases， a new monoclinic Y2O3 phase with a （111） crystal orientation emerges. Scanning electron microscopy （SEM） observations indicate that the Y2O3 films under different Zr doping powers display a columnar crystal structure with good crystallinity. Atomic force microscopy （AFM） results confirm that the Zr-doped Y2O3 films have a lower root mean square （RMS） roughness compared to the undoped Y2O3 films. In the Zr-doped Y2O3 films， the grain size of the columnar crystals significantly decreases with increasing Zr concentration. X-ray photoelectron spectroscopy （XPS） results demonstrate that metallic Zr interacts with oxygen， existing in the form of Zr-O compounds within the Y2O3 films. In the long-wave infrared range of 8-12 μm， the maximum transmittance of Zr-doped Y2O3/diamond films increases by 19.7%， while in the mid-wave infrared range of 3-4 μm， it improves by 25.9%. The fine-grained Zr-doped Y2O3 films exhibit higher hardness and elastic modulus， with increases of 5.3 GPa and 33.9 GPa， respectively.
Addressing the critical requirements for bridge fire protection， we employ sol-gel and supercritical drying techniques to fabricate high-silica fiber/SiO2 aerogel composites. Utilizing SEM， XRD， TEM， electronic universal testing machines， and thermal conductivity analyzers， we investigate the microstructure， mechanical properties， and thermal insulation capabilities of these composites after undergoing high-temperature treatment. Furthermore， we explore the thermal insulation performance of these composites in fire environments. The findings reveal that the high-silica fiber and SiO2 aerogel within the resultant composite are seamlessly integrated， with the fiber being encapsulated by the aerogel. However， following a 2 h treatment at temperatures ranging from 800-1000 ℃， the fiber surface roughens， the aerogel fractures， and portions of the fiber become exposed. Additionally， the SiO2 aerogel’s pore size expands， its specific surface area diminishes， and crystallization occurs upon high-temperature treatment. Consequently， the mechanical strength and thermal insulation properties deteriorate， with the fracture force decreasing from 130.2 N to 50.2 N and thermal conductivity increasing from 0.0163 W/（m·K） to 0.0311 W/（m·K） when comparing the untreated and 1000 ℃-treated states. Notably， cable models shielded by a 10 mm-thick high-silica fiber/SiO2 aerogel composite can maintain temperatures below 300 ℃ for up to 78 min. This research contributes valuable insights into the development and assessment of innovative fire-resistant materials for bridges.
Semiconductor photocatalytic materials exhibit significant potential for application in environmental protection，attributed to their eco-friendly and energy-efficient attributes. Ag3PO4 has garnered considerable attention owing to its superior light responsiveness and robust catalytic properties. Nevertheless，Ag3PO4 nanoparticles are prone to aggregation and difficult to retrieve，thereby hampering their practical implementations. In this study，Ag3PO4 nanoparticles are synthesized via the precipitation method，employing sodium alginate （NaAlg） as a carrier to disperse Ag3PO4 into an aqueous NaAlg solution，yielding a casting solution. Utilizing oxalic acid （OA） as a crosslinking agent，OA@NaAlg@Ag3PO4 photocatalytic membranes are fabricated and subsequently characterized for their structural and functional properties. Notably，the membrane maintains its integrity in a 10 g/L NaCl solution，whereas the calcium alginate membrane exhibits swelling and rupture，highlighting its exceptional salt tolerance. Under UV light exposure，the OA@NaAlg@Ag3PO4 membrane demonstrats a degradation efficiency of 90% for a 10 mg/L methyl orange solution containing 10 g/L NaCl within 15 minutes. Furthermore，the OA@NaAlg@Ag3PO4 hydrogel membrane exhibits a degradation rate exceeding 90% for 10 mg/L concentrations of methylene blue，malachite green，orange G，amaranth red，and rhodamine B. In comparison to Ag3PO4 nanoparticles，the composite hydrogel membrane offers enhanced operability and can be regenerated by recovering Ag3PO4.
Photocatalytic technology has received extensive attention from researchers because of its low cost，recyclability，and environmental friendliness. However，the photocatalytic performance of pure photocatalytic materials has certain defects，such as high electron-hole pair recombination rate and a small light response range. Therefore，these materials are often modified for practical applications. To improve the degradation performance of graphite phase carbon nitride （g-C3N4） for NO under visible light conditions，Fe/S co-doped modified g-C3N4 product Fe/SCN is prepared by thermal polymerization using melamine，thiourea，and iron nitrate as raw materials. It is found that Fe/S co-doping would destroy the triazine ring structure of g-C3N4，resulting in the disappearance of N—H bond stretching in g-C3N4，and Fe and S elements mainly existed in the form of Fe—N and Fe—S covalent bonds. At the same time，Fe/S co-doping can increase the specific surface area of g-C3N4，improve the separation efficiency of photogenerated carriers，reduce the recombination rate of electron-hole pairs，increase the transient current density，and reduce the electrical impedance，thereby improving the photocatalytic degradation performance. The experimental results of photocatalytic degradation of NO show that the degradation rate of NO by Fe/SCN-4 can reach 40.26% under visible light conditions for 2 h，and the degradation rate is 37.17% after 5 cycles，proving Fe/SCN-4 has good degradation performance and cycle stability.
Bacterial cellulose （BC）-based flexible conductive membrane materials have garnered significant attention in current research due to their exceptional mechanical properties， excellent biocompatibility and environmentally friendly processing technology. These materials feature a three-dimensional mesh structure with numerous hydroxyl groups on the BC fibers. However， this structural characteristic can lead to the absorption of bound water， negatively impacting charge transport. To address this issue， researchers have developed flexible conductive composite membrane materials （BC/PPy/PVA-nFG） through in-situ polymerization and vacuum filtration. In this composite， polyvinylalcohol （PVA） serve as the mechanical reinforcement component， polypyrrole （PPy） act as the conductive phase and fluorinated graphite （FG） provide hydrophobic properties as well as conductivity. By reducing the hydrogen bonding between water molecules and the hydroxyl groups on the BC fibres， the content of bound water is effectively minimized， thus enhancing the charge transport stability even in wet conditions. Experimental data reveal that the initial resistance of the dry-state flexible conductive material is 32 Ω. Upon water absorption， the resistance increases to 47 Ω at the water absorption reach 53%， demonstrating the efficacy of incorporating cost-effective FG nanosheets. This research opens up valuable avenues for developing a new generation of green and environmentally friendly flexible conductive membrane materials.
Owing to the poor interfacial interaction and weak dispersion of conductive materials in polymer matrix in flexible strain sensors， sodium alginate（SA） is used as a dispersant to modify carbon nanotubes（CNTs） and prepare conductive ink. Then， the elastic fabric is combined with the conductive ink using a dip coating method and treated with calcium chloride solution to obtain the conductive fabric. The effects of sodium alginate modified carbon nanotubes on the morphology， structure， and conductivity of conductive fabrics are studied using SEM， Raman spectra， resistance testing， and mechanical property testing. The results show that SA can improve the dispersion of CNTs in aqueous solution， and enhance the uniformity of carbon nanotubes on fabrics， and thus prepare elastic conductive fabrics with both water resistance， conductivity， and excellent mechanical properties. Sensitivity tests show that the elastic conductive fabric based sensor exhibits excellent strain and pressure sensing behavior， with a gauge factor of 3.82 along the longitudinal stretching direction of the woven fabric （0%-8% strain）， exhibits different resistance responses at 0%-30% strain， and the pressure sensing sensitivity is 0.65 kPa-1 at 0-1 kPa.
To investigation the effect of the microstructure and electrochemical behavior of the β-MnO2 samples under high-energy ball milling. The crystal structure， particle morphology， size， and atomic arrangement of the sample are measured and analyzed by XRD， SEM， laser particle size analyzer， and TEM. The electrochemical performance， electrochemical impedance spectrum， and CV curve of the sample cell are measured by battery tester and electrochemical workstation. The results show that compared with the sample before ball milling， the phase structure space group of the sample after ball milling changes， the grain size and particle size are reduced， and the coexistence of crystalline and amorphous microstructure is formed. With the increase of ball milling time， the specimen particle morphology changes to fine dispersion → particle agglomeration and dispersion → particle agglomeration and platelet， while the lattice distortion is gradually serious. The number of cycles to reach the maximum discharge capacity of the specimen cell after ball milling is reduced， the discharge efficiency of all specimens is good. However， the maximum discharge capacity is related to the grain size， particle morphology， and lattice distortion caused by the ball milling time. In different ball milling time， the maximum discharge capacity of the as-milled sample cell at 4.0 h is relatively high. After 100 charge and discharge cycles， the capacity maintenance rate of the as-milled sample cell at 5.5 h is relatively good. According to the kinetic study， it is found that the charge transfer impedance and Warburg diffusion impedance of the 4.0 h as-milled specimen cell are relatively small and the peak area of cyclic voltammetry is relatively large compared with other cells， which further indicates that the specimen cell has a relatively high electrochemical capacity and a relatively small charge/discharge potential difference. Therefore， within the scope of this study， starting from capacity and capacity retention rate， the suitable ball milling time for β-MnO2 samples is 4.0 h.
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