• Luwei DENG , Xue GONG , You WANG , Jin JIA , Feifei ZHOU , Fushuang WEI , Fei XIAO , Xiaodong ZHANG
    Journal of Materials Engineering. 2025, 53(11): 11 -29.

    Key components of high-end equipment are often exposed to harsh wear, corrosion or high-temperature environments, thus requiring higher wear resistance, corrosion resistance and high-temperature resistance. As one of the most promising surface engineering technologies at present, thermal spraying technology can be widely applied to many key components of high-end equipment to achieve the purpose of improving their surface performance. Nano thermal spraying technology is an important means to effectively combine nanomaterials and thermal spraying technology to achieve material surface modification. It is also an effective solution to extend the service life of aircraft, ships, and other high-end defense equipment in extreme environments. Nanostructured powder re-granulation technologies enable precise control over the phase composition and microstructure of thermal spray feedstocks at the nano-micro scale. This facilitates the fabrication of nanostructured coatings with tailored properties to meet diverse surface performance requirements for critical components in advanced equipment. This paper briefly summarizes the development status of nanostructured coatings with different functional orientations prepared by thermal spraying at home and abroad in the recent decade, mainly including nanostructured wear-resistant and corrosion-resistant ceramic coatings, nanostructured thermal barrier coatings, nanomodified MCrAlX alloy coatings, nanomodified WC-Co based cermet coatings and nanostructured environmental barrier coatings, etc. The results show that nanostructured and nanomodified thermal spray coatings have a very good potential to be applied on key components of high-end equipments, which can be used to meet the various surface properties required by key component of high-end equipment. key components of high-end equipment have very broad application prospects. To realize the wide application of nanostructured coatings, further research work needs to be carried out in the future in the areas of practical engineering application research, marine environmental service, marine biofouling, advanced powder preparation technology research, and high-performance powder industrialization.

  • Ruiqi WU , Chengbao LIU , Feng CHEN , Yongbin QIU , Xianrong MENG , Zhigang CHEN
    Journal of Materials Engineering. 2025, 53(11): 204 -214.

    This study utilizes mushroom stalks as a biological template and melamine as a precursor for carbon nitride to synthesize g-C3N4/C,via thermal polymerization method. Copper sulfate pentahydrate (CuSO4·5H2O),ammonium molybdate tetrahydrate ((NH46Mo7O24·4H2O),and thiourea (CH4N2S) are selected as the sources for Cu,Mo,and S,respectively. A two-step hydrothermal process is employed to prepare CuS/MoS2 composites with different mass ratios. Then CuS/MoS2 is anchored on the surface of g-C3N4/C to obtain CuS/MoS2-g-C3N4/C composite electrode materials. The composite electrode materials are characterized by their phase structure,microstructure,pore structure,and capacitance performance. The results indicate that the CuS/MoS2-g-C3N4/C composite electrode materials exhibit high purity,good crystallinity,good phase contact interface, and abundant porous structure. In electrochemical performance testing,the CuS/MoS2 composite material with a mass ratio of MoS2 to CuS at 1∶2 demonstrates optimal electrochemical performance,achieving a specific capacitance of 230 F·g-1 at a current density of 1 A·g-1. When the mass ratio of CuS/MoS2 to g-C3N4/C is 1∶1,the CuS/MoS2-g-C3N4/C composite material exhibits the best electrochemical performance,with a specific capacitance of 434.7 F·g-1. Moreover,after 1000 cycles,the capacitance retention rate is 89.2%,showing good stability.

  • Chengwei HU , Qian CAO , Hu YANG , Xudong CHENG , Xian ZENG
    Journal of Materials Engineering. 2025, 53(11): 215 -222.

    The MnO2 and VB2 co-doped NiCr2O4 coatings(MV) with different ratios of moles are prepared by atmospheric plasma spraying(APS), and the phase composition, microstructure, infrared emissivity and thermal shock resistance of the coatings are investigated. The results show that the co-doping of NiCr2O4 with MnO2 and VB2 can more effectively improve the infrared emissivity of the coatings than the doping of MnO2 or VB2, thus the coating with MnO2 and VB2 doping ratio of 1∶1 (MV11) has the highest emissivity. In the 0.75-2.5 μm wavelength ranges, the room temperature band emissivity of the MV11 coating is 0.928, and in the 2.5-25 μm, the infrared emissivity of the coating increases from 0.884 at room temperature to 0.918 at 1000 ℃. It is mainly attributed to the transition metal ions and B ions enter the spinel lattice, increasing the concentration of oxygen vacancy in the lattice, introducing partial energy levels into the bandgap, and causing lattice distortions, enhancing free carrier transition absorption and infrared lattice vibration absorption. In addition, after 30 thermal cycles of water cooling at 25-750 ℃, microcracks appear in the coating, but the phase structure did not change significantly, and the emissivity decreases slightly, indicating that the coating has good thermal shock resistance.

  • Derong FENG , Xuemin GAO , Zirui YIN , Qinying ZHANG , Guoyu FU
    Journal of Materials Engineering. 2025, 53(11): 153 -163.

    With the widespread application of carbon fiber reinforced polymer (CFRP) in the aerospace field, studying the friction performance at the interface of CFRP and aluminum alloy connections has become increasingly important. This study experimentally investigates the influence of surface microtexture parameters on the friction performance at the aluminum alloy-CFRP interface. The results indicate that both contact pressure and microgroove geometric parameters significantly affect the interface friction performance. As the contact pressure increases from 7.5 MPa to 30 MPa, the sliding friction coefficient significantly decreases, primarily due to the formation and enhancement of a self-lubricating film. Under high contact pressure, the microstructures on the aluminum alloy surface embed into the CFRP plate, creating a plowing effect. The micro-cutting action generates epoxy resin debris that fills the microstructure grooves, forming a stable lubricating film. The groove depth has the most significant impact on friction performance, with a groove depth of 31.8 μm significantly reducing the sliding friction coefficient to 0.197. The synergistic effect of contact pressure and microtexture geometric parameters markedly improves the interface friction performance and connection strength. This study provides theoretical basis and practical guidance for optimizing composite material connection technology.

  • Zhibin HAN , Lianjie MA , Yinming JIANG , Hancun JIANG , Jing JIA , Yanqing TAN
    Journal of Materials Engineering. 2025, 53(11): 174 -181.

    Based on the current status and requirements of wear in zirconia ceramics, in response to the problem friction reduction performance of single-textured specimens, different texture types are combined to extract biomimetic contours from biological surfaces and design various novel composite biomimetic textures. The numerical simulation and the experimental investigation methods are used to analyze the friction reduction performance of composite biomimetic textures,solving the Reynolds equation numerically, studying the influence of composite texture types on oil film load capacity, pressure distribution area, and maximum static pressure, and conducting experimental exploration of the tribological performance using a friction and wear testing machine. The results indicate that composite biomimetic textures exhibit higher oil film load capacity, wider pressure distribution areas, and lower friction coefficients compared to other texture types, among them, the comprehensive anti-friction effect of the scale + feather composite texture is the best; the friction reduction mechanism of composite biomimetic textures can be mainly attributed to changes in contact stress points, the asymmetric distribution of pressure and abrasive storage properties, and the form of pressure distribution of composite texture is highly dependent on a single texture type.

  • Chenying SONG , Mengru LIU , Li CHEN , Ling MENG , Shuangshuang ZHAO , Hailong LI , Jian HU
    Journal of Materials Engineering. 2025, 53(11): 197 -203.

    The preparation of carbon paper used phenolic resin as matrix carbon, and different heat treatment temperatures (1400-2700 ℃) are used to obtain matrix carbon with different structures. At the same time, the effect of matrix carbon content and structure on carbon paper for proton exchange membrane fuel cell is studied. The results show that the matrix carbon in carbon paper is more prone to graphitization transformation than carbon fiber. As the content of the matrix carbon increases, the d002 diffraction peak of the carbon paper becomes sharper. When the heat treatment temperature increases from 2100 ℃ to 2400 ℃, the graphitization of the carbon paper increases by 45.2%, which is the largest increase. With the increase of heat treatment temperature, the carbon papers, with different matrix carbon ratios, show differences in performance trends. When the carbon content of the matrix is 60%(mass fraction, the same below) and 120%, the thickness of the carbon paper gradually decreases with the increase of the graphitization temperature, and the tensile strength of the carbon paper has a slight change; when the carbon content of the matrix is 200% and 350%, with the increase of graphitization temperature, the thickness of carbon paper decreases slightly and then increases, and the tensile strength of carbon paper decreases rapidly. The surface resistivity of carbon paper shows a downward trend with the increase of heat treatment temperature, and its change trend is basically consistent with the change trend of thickness. Therefore, when preparing carbon papers with different properties, it is necessary to consider the synergistic effect of matrix carbon content and structure.

  • Wuhua HUANG , Can CHEN , Caixue LIAO , Xi LI , Changshui ZHANG , Junlong TIAN
    Journal of Materials Engineering. 2025, 53(11): 231 -238.

    Lead sulfide quantum dots (PbS QDs) have excellent optoelectronic properties and strong near-infrared light absorption,making them ideal materials for the preparation of near-infrared photodetectors. However,there are still challenges in the process and insufficient performance of the PbS QDs-based optoelectronic detection. In this study,PbS QDs are synthesized by the hot injection method,and the PbS quantum junction infrared detector is prepared by the layer-by-layer method and the solid-state ligand exchange method. The photoelectric performance of the PbS quantum junction infrared detector is improved by the thermal annealing process,and the effect of annealing temperature on the photoelectric performance of the PbS quantum junction is described. The results show that annealing effectively reduces the dark current of the PbS quantum junction infrared detector while increasing the photocurrent,and obtains a stable photoresponse current output. After annealing,the response time of the PbS quantum junction infrared detector is shortened,resulting in a time of 1.9 ms and a delay time of 3.2 ms. The sensitivity of the detector is improved,and the responsivity and detectivity are increased by 1.2 times and 1.3 times,respectively,resulting in a responsivity of 0.78 A·W-1 and a detectivity of 7.8×1011cmHz1/2W-1. Annealing effectively improves the crystallinity and the carrier mobility of PbS QDs thin films,while reducing the defect states at the film and interface,resulting in a comprehensive improvement in the optoelectronic performance of PbS quantum junction infrared detectors.

  • Yi LIU , Cheng ZHU , Zihui BAN , Yingju LI , Yaxin FENG , Zhentao ZHANG , Yuansheng YANG
    Journal of Materials Engineering. 2025, 53(11): 63 -71.

    Microstructures and mechanical properties of GH4169 alloy cylinder and its weld joints in a supercritical water reactor are studied after operating 2000 h. The results show that the GH4169 alloy cylinder exhibits good corrosion resistance under conditions of high temperature, high pressure, and sucrose mixed solution; the thickness loss rate of the cylinder is 0.005-0.255 μm/h; the corrosion products primarily consist of oxides and phosphates. However, the welded joints connecting the cylinder and other components represent a vulnerable point that significantly impacts the remaining lifespan of the reactor. The calculated crack propagation rate of the GH4169 alloy cylinder is 5.25 μm/h, indicating that it would only take 762 h for the crack to penetrate through the wall of the connector. Additionally, severe fracture occurs (the circumferential length of the crack is approximately 1/4 of the circumference) at the weld joint between cylinder and stainless-steel, resulting from the synergistic effects of galvanic corrosion, crevice corrosion, and concentrated stress. Despite these challenges, the strength loss of the cylinder is relatively small, which means that the cylinder maintains satisfactory mechanical properties.

  • Qingxue ZHANG , Qi WANG , Chengru LI , Xiangtao DENG , Zhaodong WANG
    Journal of Materials Engineering. 2025, 53(11): 101 -112.

    To develop high-temperature wear resistant steel with high tempering stability that can be used in high temperature environments, the bond energy between different alloying elements and C element is calculated by solid and molecular empirical electron theory, and a series of TiC particle-reinforced high-temperature wear-resistant steel components are designed. The precipitation temperature of TiC particles is calculated by Thermo-Calc software and the tempering stability of the steel plate after the best heat treatment is tested at different temperatures and time. The results show that the bond energy formed by Cr, Mo, and W with C is significantly higher than that of Fe—C. Therefore, the activation energy of C atom diffusion in martensite increases, which hinders the diffusion of C atom in martensite and improves the tempering resistance of martensite. Therefore, Cr, Mo, and W are determined as the main addition elements to improve the thermal stability of TiC-reinforced martensitic wear-resistant steel. TiC particles precipitate in the temperature range of 1400-1500 ℃, and the particle morphology shows that the particles distribute like grain boundaries. After thermomechanical processing, micron TiC particles can uniformly distribute on the matrix. The experimental results of tempering stability show that the addition of Cr and W elements greatly improves the tempering stability.

  • Liang LIU , Zhendong CHANG , Zhigang WANG , Rende MU , Yan CAI , Min XIE , Xiao PENG , Xiaoyong SHU
    Journal of Materials Engineering. 2025, 53(11): 182 -188.

    8%(mass fraction)Y2O3 partially stabilized zirconia (8YSZ) is a currently commonly-used top-coat material for thermal barrier coatings (TBCs) applied to turbine blades in aero-engines. However, its volume change induced by high-temperature phase transitions above 1200 ℃ can easily lead to cracking and failure of TBCs. Sc2O3 is employed as an alternative stabilizer to fabricate 8%Sc2O3-92%ZrO₂(mole fraction) ceramics (8SSZ) via a solid-state synthesis method. The thermophysical properties of 8SSZ and conventional 8YSZ, including thermal expansion coefficient (CTE), thermal conductivity, and high-temperature phase/grain stability, are systematically compared. The results show that after heat treatment at 1400 ℃ in a muffle furnace, the CTE of 8SSZ measured by a dilatometer ranges from 8.91×10-6 K-1 to 10.7×10-6 K-1, which is comparable to that of 8YSZ. Thermal conductivity tests reveal that 8SSZ exhibits a thermal conductivity of 2.59 W/(m·K), approximately 20% lower than that of 8YSZ. X-ray diffraction (XRD) and scanning electron microscopy (SEM) results demonstrate that 8SSZ maintains phase stability without phase transitions after 500 h at 1400 ℃, outperforming 8YSZ in high-temperature phase stability. However, 8SSZ still exhibits the issue of excessive grain growth.

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