Solid oxide fuel cell (SOFC) is a green and efficient electrochemical energy conversion device. Due to the use of solid ceramics as electrolyte materials, it needs to work in a high temperature environment of 600-1000℃. The high temperature environment can accelerate the aging of equipment materials, resulting in the rapid decline of battery performance. Intermediate and low temperature SOFC technology can improve the startup speed of the system, improve the durability of the equipment, and expand the scope of equipment selection. Therefore, the development of intermediate and low-temperature SOFC technology is crucial to achieve its commercial application. Since charge transfer and oxygen exchange reactions in solid electrolytes are thermal activation processes, the decrease of SOFC operating temperature can increase the ohmic polarization of the electrolyte and increase the polarization loss of the electrode, which can affect the actual power of SOFC. In recent years, the research of SOFC technology at intermediate and low temperature has mainly focused on optimizing the microstructure and chemical composition of electrodes and electrolyte materials. In this work, the research progress on the SOFC key materials for electrode and electrolyte to intermediate and low temperature is systematically summarized, and the future design and development direction of SOFC key materials are prospected.

The application of TA3 alloy in the aerospace field is mainly through welding and the microstructure and mechanical properties of its welded joints have a significant impact on the service safety of welded components. This study compared the tensile properties of the base metal and weld specimens, and studied the deformation morphology before and after tension using the scanning electron microscopy combined with electron backscatter diffraction. The results show that, unlike the equiaxed α grains in the base metal area, massive, acicular and serrated α grains are formed in the weld area. Tensile experiments show that, as a result of the hardness is significantly higher than the base area of weld area, result in welded joint fracture is located in the base area. The deformation mechanism of the weld zone is deformation twin (0112 ̅)[0111 ̅]、and(11 ̅02)[11 ̅01]. The deformation mechanism of the base metal zone is deformation twin (11 ̅02)[11 ̅01] and dislocation slip.

Facing the development demand of clean and efficient utilization of coal in the future, the development of C700R-1 alloy rotor forgings with a diameter of Ø850mm for advanced ultra-supercritical steam turbine rotor was carried out. We successfully manufactured the rotor forging by closed upsetting + extrusion method. The grain size of the forged forging was NO. 4-7, which became about NO. 3 after heat treatment. Due to the rapid cooling rate of the edge parts after solid solution, a large number of uniform and fine γ' phases could be precipitated in the subsequent aging process. Therefore, the tensile properties of edge position were slightly better than those of the heart and 1/2R position. The variation of tensile properties in different directions of edge position was small. The room temperature tensile strength could reach 950MPa, the yield strength could reach 600MPa, and the impact energy was beyond 70J at different positions after heat treatment. The tensile strength could reach 750MPa, yield strength could reach 500MPa at 700℃.The plasticity was higher than 25% at room temperature and 700℃. The creep life exceeded 7000h in the condition of 700℃/300MPa. We realized the homogeneous manufacture of large section nickel base alloy forging with diameter of Ø850mm. Through the deformation mode of closed upsetting+ extrusion and reasonable heat treatment process, we have realized the homogenization manufacturing of nickel base alloy forgings with a section grade of Ø850mm, which provides key data for the subsequent manufacturing of full-size nickel base alloy rotor forgings.

The micro-sized second phase and recrystallization structure have important influence on the strength and toughness of 5083-O alloy. In order to acquire the morphological feature of the micro-sized second phase particles and recrystallized particles in 5083-O alloy, multi-slices EDS data at low acceleration voltage of 5kV and EBSD data at 20kV of the alloy were collected basing on the double beam microscope system. These multi-slices data were restructured into three-dimensional type by Avizo software. The size, morphology, distribution, volume fraction of the chief second-phases (Mg₂Si phase and Fe-rich phase) and recrystallize structure were obtained through the restructured data. The results show that the volume fractions of Mg₂Si phases, Fe-rich phases and recrystallize particles in the studied alloy are 0.46%,0.25%, 11.7%, respectively. Most Mg₂Si particles having smooth surfaces, which are nearly spherical, nearly ellipsoid, or rod-shaped, were elongated along the rolling direction. Most Fe-rich particles, which are angular or subangular, have lower spherical degrees relatively. The three-dimensional EBSD restructure data show that the smaller size recrystallized particles have the higher spherical degrees, and vice versa. It was founded that the recrystallized grains grow up from the small sphere recrystallized particles during the annealing process, associated with the fastest growth rate in the rolling direction. The morphology of recrystallized particles is reflected by three-dimensional EBSD results more truly than the two-dimensional EBSD which may identify the consistency of the recrystallized particles incorrectly.

Wire based friction stir additive remanufacturing method was proposed to solve the inevitable occurrence of large-size cracks and damage of aluminum alloy components during production and employment. The process was achieved by designed the main W- FSAR tools include a storage chamber with a wire feeding port, a screwed transport structure, and two stirring probes. The grooves with a width of 10 mm and depth of 2 mm were successfully filled and repaired for aluminum alloy components. The results indicate that the repaired sample has high repair efficiency, smooth morphologies, homogeneous microstructure and excellent mechanical performance. The grains are refined by the dynamic recovery and recrystallization process, with a size of 1.59μm. The ultimate tensile strength and elongation reached (410±8) MPa and (11.9±0.9) %, which are increased by 26% and 159% compared to worn-out specimens. The fracture morphology represent lots of dimples, exhibiting typical ductile fracture characteristics.

Environmental barrier coatings (EBCs) are a key protective technology for the ceramic matrix composites (CMCs) hot end components of high-performance aircraft engine, which can significantly improve the service stability and reliability of the components. In this paper, Si/Yb2Si2O7/Yb2SiO5 tri-layer structural EBCs are prepared by air plasma spray (APS) and their corrosion behavior and degradation mechanism under 1350 ℃ and cycling water vapor conditions are investigated. The results show that the as-annealed coating is mainly composed of monoclinic Yb2SiO5 phase and cubic Yb2O3 phase, with nano-sized Yb2O3 phase disperses in Yb2SiO5. The surface of Yb2SiO5 coating exhibits a ridge-like structure accompanied by a certain number of pores after cyclic water vapor corrosion, and the content of corrosion products Yb2Si2O7 increases with the number of cycles. The formation of Yb2Si2O7 is related to the alternating wet to dry corrosive environment and the gaseous substance Si(OH)4. Penetrating cracks exists within the Yb2SiO5 coating but terminates at the Yb2SiO5/Yb2Si2O7 interface, and the SiO2 film generated from the oxidation of the Si bond coat is well bonded to the Yb2Si2O7 interlayer and the Si bond coat in general. The tri-layer EBCs system in this paper exhibits excellent resistance to cyclic water vapor corrosion at 1350 ℃.

A new type of Ni-20W-20Cr heterogeneous seed with low melting point, low segregation, and cellular branching characteristics was designed by Pandat thermodynamic software combined with high-throughput experimental method using Ni-20W binary alloy as the base alloy. DSC results showed that the temperature of the solid and liquid line for Ni-20W-20Cr heterogeneous seed were 1399.7 ℃ and 1419.1 ℃, respectively. Compared with the traditional seed, it existed a narrow solidification interval as 19.4 ℃. In addition, the primary spacing of the Ni-20W-20Cr heterogeneous seed during the growth was also calculated. The results showed that the primary spacing had experienced a first increasing and then decreasing process, which was in good agreement with the KF model (111±8.37μm→116±4.77μm→125±6.41μm→105±3.65μm). After that, based on the interface instability model, the transition rate for the flat interfacial instability and the cellular branching were calculated. The results showed that the flat interfacial instability transition rate in the experiment matched the model well, but the cellular branching transition rate in the experiment was higher than that in the model, which indicated that the traditional primary spacing model might not be suitable for the step incremental speed experiment. At the same time, the EDS results showed that the Cr elements were mainly concentrated on the inter-dendrites, and W elements were enriched in the dendritic stem, while Ni element was basically even distributed. At last, Ni-20W-20Cr heterogeneous seed with a cellular-dendritic structure was prepared. And it was proved that the Ni-20W-20Cr heterogeneous seed could be re-used during the preparing of the single crystal blades.

Nanomaterials with combined photothermal-chemodynamic therapy (PTT-CDT) offer significant advantages in cancer treatment, yet designing and fabricating such multifunctional nanomaterials remains challenging. In this study, cuttlefish ink (M) was used as a core, onto which a layer of CuO was grown, successfully constructing the M@CuO composite multifunctional nanomaterial. The M@CuO exhibited a spherical shape with a nanoparticle size of 128.2 nm and demonstrated excellent photothermal conversion efficiency (ηT = 47.6%) under near-infrared (NIR) light irradiation. Additionally, the M@CuO showed a strong Fenton effect at room temperature (25°C), and the Fenton reaction rate could be further enhanced by the photothermal effect, with the reaction rate at 45°C being 2.3 times that at 25°C under the same conditions.In vitro cell experiments reveal that M@CuO had good biocompatibility and could effectively kill tumor cells through combined PTT-CDT. Therefore, M@CuO provided an effective strategy for developing multifunctional nanomaterials with PTT-CDT synergistic therapy.

Mesoporous bioactive glass (MBG) has promising application in the field of bone repair, due to its good biological activity, high specific surface area and ordered mesoporous structure. Adding therapeutic inorganic ions or organic molecules can achieve functional biological properties. Through a microemulsion-assisted sol-gel method, we synthesized radially structured mesoporous bioactive glass composite microspheres doped with copper ions (contents of 1 mol%, 3 mol%, and 5 mol% respectively). The composite microspheres retained the original spherical morphology and mesoporous structure of MBG, with pore size of 10-20 nm and particle size of 250-310 nm. The specific surface area of ​​copper-containing MBG decreased with the increase of copper ion, from 1Cu-MBG 336.5 m²/g to 5Cu-MBG 149.1 m²/g. Simulated body fluid immersion experiments showed that the composite microspheres quickly induced the formation of apatite and showed good biological activity. Antibacterial experimental results showed that the introduction of copper significantly improves the antibacterial properties of MBG. As the copper content increased, the antibacterial properties of the composite microspheres were enhanced. Among them, the antibacterial rate of 5Cu-MBG reached above 80 % after co-cultured with E. coli for 24 hours.

This paper aims to compare the changes in residual flexural strength after surface damage in chemically strengthened lithium aluminosilicate glass and chemically strengthened aluminosilicate glass. The single-particle sandblasting damage and multi-particle sandblasting damage of chemically strengthened lithium aluminosilicate glass and chemically strengthened aluminosilicate glass were prefabricated by a self-made sandblasting tester at different pressures. The bending strength before sandblasting and residual flexural strength after sandblasting damage were tested. The results show that the depth of compressive stress layer of chemically strengthened lithium aluminosilicate glass is significantly greater than that of chemically strengthened aluminosilicate glass. The compressive stress of aluminosilicate glass and lithium aluminosilicate glass after chemical strengthening varies differently along the thickness direction. The compressive stress of aluminosilicate glass is greater than that of lithium aluminosilicate glass within 40 μm depth range, while the compressive stress of lithium aluminosilicate glass is greater than that of aluminosilicate glass when the depth exceeds 40 μm. After sandblasting damage, the residual flexural strength of aluminosilicate glass is greater when the damage depth is within 40 μm depth range, while the residual flexural strength of lithium aluminosilicate glass is greater when the damage depth is further increased to more than 40 μm. Chemically strengthened lithium aluminosilicate glass has a greater advantage in residual flexrual strength after surface damage compared to aluminosilicate glass.

In order to study the impact of the microstructure and electrochemical behavior of the high-energy ball mill on the β-MNO₂ samples, XRD, SEM, Lidar size analyzer, TEM test and analyze the structure, particle appearance and size, and crystal structure of the sample; The electrochemical performance, electrochemical impedance spectrum and CV curve of the battery tester and electrochemical workstation are used to test the battery. The results show that compared with the sample before the ball grind, the crystal structure space group of the sample after the ball is changed, the grain size and particle size are reduced, and the microstructures that coexist in crystal and amorphous state. As the ball grinding time increases, the form of the sample particles is to be small-scattered-granular reunion and decentralization-granular reunion and plate transformation, and at the same time, the lattice distortion gradually becomes serious. The activation performance and discharge efficiency of the sample battery after the ball grind are good, but the maximum discharge capacity is related to the microstructure and particle form of the ball mill time. In different ball mills, the maximum discharge capacity of the 4.0h ball grinding sample battery is relatively high. After 100 charging and discharge cycle, the capacity maintenance rate of the 5.5h ball grinding sample battery is relatively good. According to dynamic studies, compared with other batteries, the charging impedance of the 4.0h ball grinding sample battery is relatively small, the WARBURG diffusion impedance is relatively small, and the peak area of the circulating ambush method is relatively large. The relatively high electrochemical capacity and the relatively small charging potential difference.

To solve the problem of the fatigue resistance short-coming of full carbon fiber reinforced polymer composites during use, and in order to make bicycle rim with the advantages of strong compression resistance, strong fatigue resistance and moderate cost, the bicycle rim with carbon/glass inter-ply hybrid fiber reinforced epoxy composites was designed and numerically analysed. Firstly, the mechanical properties of fiber and epoxy was used in unit cell theory to calculate the orthotopically mechanical properties of continuous fiber reinforced composites, as the input parameters of ABAQUS software. Then, the effects of the variation of the hybrid ratio and stacking sequence on the mechanical properties of bicycle rim in-service was calculated by the hybrid ratio and tacking sequence of the side wall and the rim bead of the bicycle rim, respectively. Multiple sets of hybrid ratio of carbon fiber (CF) and glass fiber (GF) and layup schemes were designed, calculated and analysed to obtain the optimal hybrid ratio and stacking sequence. It demonstrates that the best hybrid ratio CF/GF of the side wall is 3:2, and the best hybrid ratio CF/GF of the rim bead is 10:16. The results of 50 000 times accelerated fatigue test demonstrate that selecting the optimal hybrid ratio layup scheme to make composite bicycle rim can significantly improve its fatigue resistance because hybrid composite can inhibit interlaminar crack.

As a method of non-destructive testing of residual stress, ultrasonic testing has been widely used in the measurement of residual stress of various metal materials and components, but ultrasonic testing is greatly affected by the microstructure of the detection material, resulting in inaccurate detection results. Based on the acoustic elasticity theory, the influence of microstructure of steel plate with different strength on ultrasonic longitudinal wave velocity and residual stress detection results was studied, and the possibility of strain in the selected test samples was ruled out by drilling method and X-ray scattering techniques.The results indicate that under stress-free conditions, ultrasonic longitudinal wave propagation speed is the fastest in ferrite, faster in pearlite and slowest in martensite, and grain size also has an effect on ultrasonic longitudinal wave speed. However, when the grains show obvious anisotropy, the influence of grain orientation on the ultrasonic longitudinal wave velocity is more significant than the influence of the structure on the ultrasonic longitudinal wave velocity. When the same steel plate is tested with different benchmarks, the error caused by the residual stress test results is about 800 MPa due to the different microstructure of the benchmarks. Choosing the stress-free benchmark which is the same as the microstructure of the material to be tested can avoid the influence of microstructure on ultrasonic testing and significantly increase the accuracy of ultrasonic testing of residual stress.

In order to improve the comprehensive mechanical properties of Selective laser melting (SLM) TA15 alloy, the microstructure and mechanical properties of SLM TA15 alloy were studied under annealing conditions of 800℃+ air cooling, 950℃+ air cooling and 1050℃+ air cooling. The microstructure characteristics of TA15 alloy under annealing conditions were characterized by electron backscatter diffraction. The results show that the orientation and texture of α phase were not changed after the heat treatment at 800℃ or 950℃, showing the characteristics of net basket structure. After the heat treatment at 1050℃, the texture with the maximum strength of 9.18 appears along the direction [0001], showing characteristic of weistenite structure. With the increase of annealing temperature: the width of both α' and α phase increased gradually; the aspect ratio of both α' and α phase increased first and then decreases; the geometrically necessary dislocation density of both α' and α phase decreased gradually; the Vickers hardness of the sample decreased first and then increased, with the highest Vickers hardness of 397.2±10HV at the unheat treated sample; the strength of TA15 sample decreased gradually; and the elongation increased first and then decreased. After tensile tests, the unheat treated samples showed mixed fracture characteristics, the samples treated at 800℃ and 900℃ showed plastic fracture characteristics, and the sample treated at 1050℃ showed brittle fracture characteristics.

According to the maximum solid solubility of Zn, Mg, Cu in aluminum and their precipitation strengthening phases, Al-12Zn-2Mg-0.5Cu-0.3Sc (wt.%) high strength aluminum alloy was designed. The billet of this alloy was hot rolled followed by clod rolling and heat treatment, to explore the optimal heat treatment process for aluminum alloy with high solid solubility in order to obtain good tensile properties. Optical microscopy (OM), X-ray diffractometry (XRD) and scanning electron microscopy (SEM) were used to observe and analyze the microstructure of the alloy under different heat treatment conditions, and universal tensile testing machine was used to test the tensile properties of the alloy at room temperature. The results show that after solution treatment at 470℃/1h, the microstructure of the cold-rolled alloy is incomplete recrystallized with elongated grains along the rolling direction. The tensile strength of the alloy is 599MPa, and the elongation reaches 15.4%, which shows that the alloy has good pre-aging properties. After aging treatment at 120℃/30h, good mechanical properties were obtained, and fine MgZn2and T(AlZnMgCu) strengthened phases are precipitated in the microstructure, which further improve the properties of the alloy. The corresponding tensile strength reaches 736MPa, and the elongation is 10.6%.

When friction stir welding steel materials, adding auxiliary heat can effectively reduce the wear of the expensive stirring tool. For this purpose, the Q960 high-strength steel was preheated to 150 ℃ and 300 ℃ by a bottom preheating device, and then the steel plate was welded by friction stir welding technology, and the microstructure and joint impact toughness were analyzed. The results indicate that the temperature difference in the direction of the plate thickness can be effectively eliminated by adding auxiliary heat at the bottom. With preheating to 150 ℃, the bottom defect of friction stir welding joint of Q960 high-strength steel disappears, however, with preheating to 300 ℃, the downforce of the stirring tool is significantly reduced, and defects are formed at the bottom of the joint. During auxiliary heating FSW, the peak temperature of the joint increases gradually, and the cooling rate decreases with the increase of the auxiliary heat temperature. At 150 ℃ low- temperature auxiliary heating, the growth of the precipitate is not obvious, the hardness is slightly reduced, and the impact toughness of the joint is obviously improved. At 300 ℃ high-temperature auxiliary heating, the joints will be tempered significantly, and the precipitates will be severely coarsened, which will lead to sharp deterioration of the impact toughness of the joint. Hence, low-temperature auxiliary heating can not only obtain defect-free joints, but also effectively improve the impact toughness of Q960 high-strength steel joints.

In order to explore the oxidation mechanism of GCr15 bearing steel under 25%CO2+75%N2 mixed atmosphere, in this paper, the oxidation kinetics of GCr15 bearing steel was investigated using simulated atmosphere and the discontinuous weighing method. The morphology and phase composition of the oxidation products were observed and analyzed using optical microscopy, scanning electron microscopy and x-ray diffractometer. The Gibbs free energies ?G of the main reactions under mixed atmosphere and experimental temperatures are estimated by thermodynamical calculation. It is shown that the oxidation weight gain increases with increasing holding time and heating temperature, agreeing with the parabolic law. The oxidation rate constants KT are 1.24, 1.53 and 2.17 mg2mm?4min?1 at aging temperatures of 1150, 1175, 1200°C, respectively. The oxidation activation energy of GCr15 bearing steel under mixed atmosphere is estimated to be 195×103kJ/mol. The thickness and the density of the oxide layers increase with the increase of holding time and heating temperature. O and Fe elements are enriched in the outer layer of the oxidation layer, and the oxidation products are mainly composed of FeO and Fe3O4. However, in the inner layer of the oxidation layer, Si, Cr and C enriched are enriched, and the oxidation products are mainly composed of FeO. It is consistent with the results from thermodynamic calculation of the oxidation products. The iron oxide particles in the outer oxidation layer are pyramid-like, and there are a few small pores for gas channels between the particles. The oxidation behaviors are controlled by the diffusion rate of reactants during the oxidation process, and the oxidation rate decreases in the late stage due to (i) isolating the atmosphere by the oxidation products, (ii) the decreasing Fe diffusion in the matrix by the pores in the inner oxidation layer; (iii) blocking the pores and reducing the gas flow by the melting silicate in the oxidation products.

Metal Matrix Composites (MMC) exhibit significant potential for applications in wear and friction reduction due to their integration of metallic ductility with the high strength, high hardness, and other properties of reinforcing phases. Traditional MMC hard coatings primarily enhance hardness and wear resistance by increasing the content of reinforcing phases. However, significant differences in physicochemical properties between the two phases often lead to the generation of large thermal stresses or phase transformation stresses within the coating, resulting in decreased coating toughness and increased crack sensitivity. Compared to traditional surface modification techniques, Laser Cladding (LC) utilizes a high-energy laser beam as the heat source, enabling rapid coating formation which favors the acquisition of fine-grained microstructures and reduces the susceptibility to coating cracking. Furthermore, graphene, with its unique two-dimensional structure and exceptional thermal, mechanical, and self-lubricating properties, can be incorporated as a reinforcing phase into metal matrices to form multiscale structural coatings. This not only enhances the coating's hardness and improves its wear and friction reduction performance but also boosts its fracture toughness. Therefore, this paper systematically reviews the influence of graphene on the microstructure evolution and tribological properties of MMC coatings, focusing on the preparation of graphene-reinforced titanium-based, nickel-based, and cobalt-based composite coatings using the laser cladding method. Initially, the paper outlines the structure and properties of graphene and summarizes common surface modification methods to address the challenge of graphene dispersion within the matrix for the preparation of graphene materials suitable for laser cladding. It then introduces the current research status of MMC wear-resistant coatings prepared by laser cladding and summarizes the friction and wear reduction mechanisms of graphene. Finally, the paper highlights several existing difficulties in the LC processing and preparation of graphene-reinforced metal matrix composite (Gr/MMC) coatings and offers prospects for further research and development in this area, aiming to provide a valuable reference for subsequent related research and practical applications.

Fe-Mn-Al-Ni based shape memory alloys exhibit an extremely low temperature dependence of the critical stress of martensitic transformation and display great superelastic temperature ranges (-263 to 240 °C). Therefore, these shape memory alloys show promising applications in aerospace, space exploration, vibration damping, and other environments with variable working conditions. In this work, the main factors affecting the superelasticity of Fe-Mn-Al-Ni based shape memory alloys were reviewed and prospected. Since the precipitation of coherent B2 nano-phase plays the key role in the martensitic transformation from non-thermoelastic to thermoelastic in Fe-Mn-Al-Ni-based shape memory alloys. The mechanism by which the coherent B2 nano-phase modulates the martensitic transformation of Fe-Mn-Al-Ni-based shape memory alloys and the related progress of its size regulation were firstly discussed. Since the superelasticity of Fe-Mn-Al-Ni-based shape memory alloys is known to be positively correlated with the grain size, the preparation of single crystals is a prerequisite for achieving excellent superelasticity. Therefore, the single-crystal growth studies of Fe-Mn-Al-Ni-based shape memory alloys in recent years were reviewed. Then, the functional properties of single-crystal Fe-Mn-Al-Ni-based shape memory alloys were summarized. Finally, the future research and development of Fe-Mn-Al-Ni-based shape memory alloys were prospected.

With the development of aviation, aerospace, and maritime fields, the service conditions of high-end equipment have become more stringent, putting higher demands on the development of manufacturing industries. Additive manufacturing technology, also known as 3D printing technology, is suitable for manufacturing complex-shaped structures. Among them, Wire Laser Directed Energy Deposition (W-LDED) is a new manufacturing technology that has received widespread attention in recent years. This technology has advantages such as high efficiency, high precision, and high material utilization, and it has a broad application prospect in the field of high-end equipment manufacturing. Although W-LDED technology has many advantages, there are still challenges in aspects such as the selection of process parameters, multiple thermal cycles, and process control and reproducibility. The quality of deposition and the stability of manufacturing are affected by multiple factors. How to improve these issues has become the focus of current research. This paper provides a detailed introduction to the research status of W-LDED technology from three aspects: process optimization, deposition quality analysis, and organizational component regulation. It analyzes the impact of different parameters on the quality of formation and manufacturing stability, proposes optimization strategies, further summarizes the current application scenarios of W-LDED technology, and puts forward a vision for the future development of this technology.

Orthogonal experiments were carried out to investigate the optimal process conditions for the preparation of Sargassum-based activated carbon with different impregnation ratios, impregnation times, activation temperatures and activation times based on the self-templated "eggshell" structure using Sargassum as the raw material and ZnCl₂ as the activator. The electrochemical properties of sargassum-based activated carbon were tested, and N₂ adsorption, SEM characterization and X-ray diffraction were used to investigate the pore structure properties, surface morphology and crystal structure of the activated carbon. The optimum process conditions for the preparation of high specific capacitance activated carbon were analyzed by orthogonal experimental method and obtained as follows: impregnation ratio of 3, impregnation time of 2h, activation temperature of 700°C and activation time of 2h. Under nine sets of experimental conditions, the prepared activated carbon SAC₇ has the best electrochemical performance, the specific capacitance of activated carbon SAC₇ is as high as 136.4F/g when the current density is 0.5A/g, and its specific capacitance is as high as 92.0F/g when the current density is 5A/g, which shows a good specific capacitance and multiplicity performance; and after 10000 cycles of charging and discharging, it still has a capacitance retention rate as high as 99.74%, with excellent cycling stability.