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  • Effect of Mo on Microstructure and Properties of AlCoCrFeNiMox High Entropy Alloy Coatings Prepared by Laser Cladding
  • Uniform Elongation and Yield-Drop Phenomenon in Magnetically Annealed 1050 Aluminum Alloy Prepared by CryoECAP
  • Effect of Heat Treatment on Microstructure and Properties of Titanium Alloy Welded Joint by Laser Welding with Flux-Cored Wire
  • Deposition Behavior of HVOF Sprayed WC-12Co Particles on AA7075
  • Effect of Primary α-Phase on Micro-area Plastic Deformation of Ti6242s Alloy Under Dwell Fatigue
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    2023,Volume 52, Issue 11

      >Special Issue:titanium alloy
    • Liang Weifeng, Lian Lixian, Lin Zifeng, Liu Ying

      2023,52(11):3715-3722 DOI: 10.12442/j.issn.1002-185X.20230229

      Abstract:Mg-Ti composite with bicontinuous phase structure was prepared by the additive manufacturing (AM) coupled with the melt infiltration. The effects of pore structure type and size parameters on the porosity and mechanical properties of AM-prepared Ti-6Al-4V (TC4) porous scaffold reinforcement were investigated. By adjusting the size parameters, both high porosity and appreciable compressive strength can be achieved for the scaffold. The strengthening effect of titanium alloy scaffold on the mechanical properties of Mg-Ti composite was investigated by analyzing the microstructure and interface bonding mechanism. Results show that the Mg-Ti composite has high compressive strength of 400 MPa, whereas its density is only 2.56 g·cm-3, presenting the potential as lightweight structural materials. The strength of Mg-Ti composite is higher than that of raw Mg-9Al-1Zn (AZ91) alloy matrix by 51%. This enhancement is attributed to the tight metallurgical bonding interface between the scaffold and the matrix, which promotes the effec-tive transfer of load. Additionally, the mutual constraint effect caused by the bicontinuous phase structure and the fine crystal streng-thening caused by the ultra-fine α'-Ti martensite in TC4 scaffold also significantly contribute to the improvement of mechanical pro-perties. The investigation strategy in this research provides a nouveau path for the development of structural lightweight composites.

    • Wang Ding, Sun Yunan, Xue Zhiguo, Zhang Penghui, Wu Jiangtao, Fan Keshe, Huang Xingli

      2023,52(11):3723-3729 DOI: 10.12442/j.issn.1002-185X.20230180

      Abstract:Titanium-steel composite plates with large sizes of 4260 mm×4260 mm×(6.5+32) mm were prepared by explosive welding technique. Ultrasonic nondestructive testing, phased-array waveform microscopy, optical microscope, and scanning electron microscope were used to analyze the mechanical properties and interface morphologies of the composite plates. Results show that when the detonation velocity, density, explosive height, and stand-off distance are 2200–2270 m/s, 0.80–0.82 g/cm3, 45.0–46.0 mm, and 8.0–11.0 mm, respectively, the mechanical properties of the prepared plates can satisfy ASTM B898-2020 technical requirements. The interface waveform presents a typical periodic combination morphology and the interface is clear and uniform. A small amount of solidified melt exists in the vortex area of waveform. The ratio of amplitude to wavelength ranges from 0.15 to 0.25, and the optimal shear strength can be achieved when the ratio is approximately 0.20. This research provides preparation technique for the large-size titanium-steel composite plates and theoretical guidance for the subsequent optimization of the explosive welding process of composite plants.

    • Gao Jian, Liu Fencheng, Liu Fenggang, You Qifan, Wei Yuhan, Cheng Shixiang

      2023,52(11):3881-3892 DOI: 10.12442/j.issn.1002-185X.20220858

      Abstract:TC4 titanium alloy specimens were prepared by laser directed energy depositon in different oxygen contents of inert atmosphere. The effects of oxygen content in the argon shielding gas on microstructure, fracture surface and mechanical properties of TC4 titanium alloy by laser directed energy depositon have been investigated by optical microstructure (OM), scanning electron microscopy (SEM) , transmission electron microscope (TEM), microhardness testing and tensile testing. The results show that the oxidation degree of the samples surface increase, and the surface color of TC4 titanium alloy samples gradually change from silver white to yellow, blue and dark gray with the increasing of the oxygen content of the atmosphere. From XRD analysis, the types of oxides on the sample surface increase, and the thickness of the oxide layers also increase gradually. The microstructure of the specimens gradually change from basket structure to acicular martensite α" structure, the laths are coarsened and the aspect ratios are reduced. The hardness and tensile strength at room temperature of TC4 titanium alloy samples increase gradually with the increase of oxygen content in the forming atmosphere. Due to the influence of metal lattice distortion and cooling rate, the tensile strength of the deposition samples increase from 920 MPa to 982 MPa and the elongation decreased from 12.4% to 10.9%.

    • lilei, Han Feixiao, Zhou Min, Shi Puying, Yin Yanfei

      2023,52(11):3909-3914 DOI: 10.12442/j.issn.1002-185X.20220869

      Abstract:The TC4 bar with a diameter of 30mm for blades was prepared by radial forging. The microstructure, phase composition and texture of the bar from the edge to the center were tested by metallographic microscope, XRD diffractometer and electron backscatter (EBSD) technology. The effects of the microstructure and texture on the uniformity of mechanical properties and the level of ultrasonic flaw detection clutter were analyzed. The experimental results show that the internal grains of radial forging bars are fully refined, and the grain size gradually increases from the edge to the center. The transformed β lamellar structure is broken during radial forging. The bar contains a small amount of equiaxed β grains, which distribute in αp grain boundary and transformed β structure. The texture of the edge is {0001}<10-10>. The texture of the R/2 and the center is <10-10>//axial direction. The texture strength of the bar weakens gradually from the edge to the center. The coefficient of variation of tensile and yield strength of the bar are only 0.24% and 0.29%, which means the excellent uniformity. The level of ultrasonic flaw detection clutter of small size TC4 bars is ? 0.8-9dB, the clutter level is higher than the rolling bar. That is related to the change of crystal orientation in the non-uniform area of the microstructure of the radial forging bar.

    • Xin Shewei, Liu Xianghong, Zhang Siyuan, Zhou Wei, Li Qian, Guo Dizi, Zhang Pingxiang

      2023,52(11):3981-4001 DOI: 10.12442/j.issn.1002-185X.20220794

      Abstract:Due to excellent mechanical properties combined with low density, good corrosion resistance and weldability, titanium alloy acts as attractive structural materials for aerospace, ship navigation, weaponry and nuclear industry now. However, it`s high cost hinders the wide use of titanium alloy in different fields, and which is the key factor for not huge production as Al and further use of titanium alloy. Aiming at low cost of titanium alloy, three parts of raw materials, alloy preparation technology and cooperation of titanium industry were overviewed. On this basis, the trends and suggestions for the development of low-cost titanium alloys in the future are put forward.

    • Chen Yuyong, Ye Yuan, Ye Yuan, Zhang Yu, Sun Jianfei

      2023,52(11):4002-4012 DOI: 10.12442/j.issn.1002-185X.20220809

      Abstract::TiAl alloy are high-profile advanced structural material because of its high strength-to-weight ratio and high service temperature, which has great potential in aerospace,automotiveandotherfields. However, TiAl alloy has poor thermal workability and is difficult to be formed by traditional methods. Powder metallurgy has a significant advantage in preparing complex TiAl alloy parts due to the characteristics of near-net forming.In recent years, researchers have done a lot of work on sintering technology of TiAl alloy powder and made some progress.The Process, microstructure,mechanical propertiesandparts of TiAl alloy using spark plasma sintering (SPS), hot isostatic pressing(HIP), hot pressing sintering,spray depositionand injection moldingin recent years were reviewed. The features and existing problems of above preparation methods were discussed. Meanwhile, some suggestions on powder metallurgy forming TiAl alloy parts and its future development were proposed.

    • >Special Issue:surface treatment technology
    • Sha Minghong, Wang Shuang, Li Shengli, Jia Chuntang, Huang Tiandang, Zhu Xiaolei, Ai Xingang, Liao Xiangwei

      2023,52(11):3685-3690 DOI: 10.12442/j.issn.1002-185X.E20230007

      Abstract:AlCoCrFeNiMox (x=0, 0.5, 1.0, 1.5, 2.0) high entropy alloy (HEA) coatings were prepared by laser cladding method. The effect of Mo content on the microstructure, hardness, and corrosion resistance of the coatings was studied. Results show that with increasing the Mo content, the microstructure is changed from (Al, Ni)-rich body-centered cubic (bcc) phase+(Mo-Cr-Fe)-rich σ phase into (Fe, Ni)-rich bcc phase+(Mo-Cr-Fe)-rich σ phase+(Al-Fe-Mo)-rich σ phase+a little AlN (aluminum nitride). Additionally, the coating hardness (HV1) is increased from 6514.4 MPa to 10652.6 MPa. With increasing the Mo addition, the self-corrosion potential of the coating in 3.5wt% NaCl solution is also increased. The coating presents the optimal corrosion resistance at x=1.0.

    • Lai Maolin, Guo Lanfang, Ge Liangquan, Zeng Guoqiang, Liu Chunhai

      2023,52(11):3691-3696 DOI: 10.12442/j.issn.1002-185X.20230022

      Abstract:FeCrAl coating with thickness of 18 μm was deposited on Zr-4 alloy substrate by magnetron sputtering in order to improve the high-temperature oxidation resistance of Zr alloys. The oxidation resistance of FeCrAl coating with low Al content was investigated by air oxidation tests. Field emission scanning electron microscope, energy dispersive spectrometer, and grazing incidence X-ray diffraction were used to evaluate the relationship between interfacial evolution and element migration. Results show that although the FeCrAl coating is layered and gradually peels off after air oxidation at 1000 °C, the coating still effectively protects the Zr-4 substrate from oxidation. The performance degradation of FeCrAl coatings is mainly caused by the severe outward diffusion of Al element and the inward diffusion of Fe and Cr elements at high temperatures, which results in the layering and peeling inside the coating. The air oxidation behavior of FeCrAl coating at 800, 900, and 1000 °C was also discussed.

    • Li Qindong, Meng Junsheng, Chen Baisen, Hao Chenfan, Chen Zhihui

      2023,52(11):3707-3714 DOI: 10.12442/j.issn.1002-185X.20230205

      Abstract:A CeO2-modified aluminide coating was prepared on 309 stainless steel by pack cementation method with NH4Cl as activator. The surface and cross-section of the coating before and after cyclic-oxidation at 900 °C for 50 cycles were analyzed by X-ray diffractometer and scanning electron microscope coupled with energy dispersive spectroscope. The microstructure analysis results show that the modified coating consists of Fe4Al13 phase. A few CeO2 nanoparticles are entrapped due to the outward diffusion of base metal. Compared with the normal aluminide coating without the addition of CeO2 nanoparticles, the aluminide coating modified by dispersed CeO2 nanoparticles has better scale spallation resistance in air at 900 °C. Some Fe2Al5 phases can be found on CeO2-modified aluminide coating even after 50 cycles of oxidation. Additionally, the outward-diffused Al layer, the intermediate FeAl layer, and the external Fe2Al5+FeAl mixed layer exist in the coating, suggesting that CeO2 nanoparticles can retard the degradation of aluminide coatings.

    • 郭晓峰, zhangzilong, qinlei, yuanbo, gaojunxiang, pangziqiang

      2023,52(11):3757-3766 DOI: 10.12442/j.issn.1002-185X.20230244

      Abstract:This work studies the influence of characteristic parameters on the heat transfer and stress distribution for the thermal barrier caotings used in a novel 700℃ dual-pipe system. The finite element sequential coupling method was used and revealed that the thickness ratio of the ceramic layers, thermal conductivity of the outer ceramic layer, thermal expansion coefficient, cooling steam temperature, and pressure simutaneously have significant effects on the temperature and stress distribution of the coated steam dual-pipe system. On this basis, a structural optimization method for the multilayer heterogeneous coating system was developed by using MATLAB and ABAQUS platforms. And the optimal geometric sizes and material properties were identified. Furthermore, it was discovered that the inner surface temperature of P91 steel pipes can be decreased by about 27℃ and the maximum Mises stress at the interface between thermal growth oxide and bond coat can be decreased by about 151MPa, respectively. The results show that the proposed systematic optimization method can be used to automatically determine the optimal key characteristic parameters of multilayer heterogeneous coating systems, resulting in improved thermal management and reduced stress on critical components. These findings have important implications for the design and optimization of thermal barrier coatings in high-temperature applications.

    • Wang Zuokai, Qi Ziheng, Li Ziyu, Ying Lixia, Wu Ruizhi, Wang Zhideng, Wang Guixiang

      2023,52(11):3873-3880 DOI: 10.12442/j.issn.1002-185X.20220853

      Abstract:In order to improve the corrosion resistance of aluminum alloy, a porous anodizing film was prepared on the surface of aluminum by anodizing method, and a magnesium-aluminum hydrotalcite (MgAl-LDH) with layered bimetallic structure was constructed on the surface by the in situ growth method using the anodic oxide film as the skeleton. For the first time, zinc dibenzyl dithiocarbamate (ZBEC) was used to modify the prepared MgAl-LDH film layer, and the morphological composition of the modified MgAl-LDH film layer was studied by SEM, EDS, XPS and ft-IR, and the effects of ZBEC concentration, modification temperature and modification time on the corrosion resistance of the modified film were studied by electrochemical impedance spectroscopy (EIS).The results show that the hydrotalcite film layer is a flaky staggered structure perpendicular to the surface of the matrix, the ZBEC molecule can successfully bind to the MgAl-LDH film layer, and the modified film layer has a good binding force. When the concentration of ZBEC modified solution was 0.03 mol/L, the temperature was 45°C, and the time was 15 min, the EIS low-frequency modulus value of the modified film layer increased from about 7.94×100000 Ω?cm2 to 1.995×1000000 Ω?cm2, indicating that the ZBEC modification improved the corrosion resistance of the MgAl-LDH film layer.

    • >Special Issue:High Temperature Alloy
    • songkun, huangxia

      2023,52(11):3767-3777 DOI: 10.12442/j.issn.1002-185X.20230187

      Abstract:Molecular dynamics simulations were used to investigate the effect and mechanism of the angle (θ) between the plane of void center formation and the loading direction on void growth and coalescence behavior in single-crystal nickel under uniaxial tension. The results show that the yield stress and average flow stress of single-crystal nickel decrease with increasing θ, and the rate of stress decrease accelerates with increasing θ. When θ=90° (loading direction perpendicular to the plane of void center), the independent growth time of voids in single-crystal nickel is the shortest and void coalescence occurs first, leading to the most easily entering the softening stage. This is due to the fastest growth rate of void volume fraction and damage evolution rate in single-crystal nickel when θ=90°. When θ=90°, the significant reduction of 1/6<112> (Shockley) dislocation length and the maximum transformation rate of atomic number from FCC crystal structure to Other and HCP crystal structures in single-crystal nickel lead to the fastest damage evolution rate and the most severe damage level when θ=90°. It is worth noting that voids in single-crystal nickel are most likely to coalesce when θ=90°, due to the larger tensile stress on the void surface under this condition. Through this work, the aim is to reveal the void coalescence behavior and mechanism of metallic materials under high strain rates, and to provide theoretical guidance for understanding their softening behavior and fracture mechanism.

    • Zhang Haiyan, Cheng Ming, Hu Rufu, Zhang Shihong, Zhao Zhong

      2023,52(11):3778-3784 DOI: 10.12442/j.issn.1002-185X.20220799

      Abstract:The spheroidization behavior and kinetic model of plate-like δ phase of DP-GH4169 alloy during hot deformation were investigated by OM, TEM and isothermal compression tests. The results show that the dissolved spheroidization behavior of plate-like δ phase is mainly controlled by the diffusion of Nb from δ/γ phase boundaries to matrix γ. In the process of hot deformation, the dissoloved spheroidization has little effect on the spheroidization behavior of plate-like δ phase. The spheroidization critical strain εc of plate-like δ phase depends on the deformation temperature and strain rate. The spheroidization critical strain εcof plate-like δ phase is from 0.04 to 0.10 in the isothermal compression tests, and it decreases with the deformation temperature increasing or the strain rate decreasing. The relationship between the spheroidization volume fraction of plate-like δ phase and the thermal deformation parameters is accord with the Avrami equation.

    • Zhao Pengfei, Wang Min, Ou Mei Qiong, MA Yingche, Liu Qui

      2023,52(11):3809-3817 DOI: 10.12442/j.issn.1002-185X.20220815

      Abstract:K4750 alloy is a new cast nickel-based superalloy with excellent mechanical properties at 700-750℃ and is expected to replace K4169 alloy. However, the tensile plasticity of K4750 alloy at room temperature fluctuates, and the relationship among room temperature tensile properties, solidification microstructure, and casting parameters is still unclear for this alloy. In this work, several K4750 alloy test bars were prepared with various casting temperatures and shell cooling conditions, and tested at room temperature by uniaxial tension. Sensitivity of the alloy"s room temperature tensile properties to changes in casting temperature and shell cooling rate was evaluated, and the mechanism was elucidated by microstructure characterization. Results show that the grain size of alloy drops significantly with decreasing casting temperature, and the yield strength of alloy slightly increases while the plasticity remains stable. When cooling rate of the shell decreases, the fracture elongation of alloy decreases significantly at room temperature. This is mainly because the cooling condition of mold shell significantly affects the precipitation characteristics of MC carbides. When the cooling rate is low, MC carbides tend to precipitate at grain boundaries in coarse and strip-like shapes. MC carbides are prone to internal cracks under stress, accelerating the intergranular failure of material and reducing the plasticity of alloy. In order to optimize the tensile properties of K4750 alloy at room temperature, more attention should be paid to the cooling rate of mold shell after casting and the precipitation morphology of intergranular carbides, prohibiting the formation of coarse intergranular carbides to improve the grain boundary plasticity of alloy.

    • Yang Wenchao, Sa Shipeng, Hao Wenshuo, Qin Jiarun, Zhang Jun, Liu Lin

      2023,52(11):3847-3856 DOI: 10.12442/j.issn.1002-185X.20220837

      Abstract:For the stray grain problem of 18 single crystal blades in high efficiency preparation due to the non-uniform temperature field, three different module structures ensure to have same production capacity were designed. The high rate solidification of DD6 Ni-based superalloy under different module structures was simulated by using ProCast software and CAFE model, the influence of the temperature field evolution and the withdrawal rate on stray grains was analyzed. The result showed that the solid-liquid interface of the single-layer module became curved seriously because the cooling efficiency of side close to the center pillar is higher than the side close to the furnace body for the heat preservation effect of center pillar is weak, and it had a large undercooling and tendency to form stray grains. By adding a sleeve to the single-layer module to increase the heat preservation effect, the temperature field can be changed effectively, the degree of bending was reduced to avoid the nucleation of stray grain. The double-layer superimposed module had a uniform thermal and a low undercooling, which could decrease the tendency of stray grain effectively. Both the double-layer superimposed module and the sleeve module could form a complete single crystal when the withdrawal rate was below 100 μm/s, however the diameter of the double-layer superimposed module reduces to a half of the other two, which could reduce the requirement of size of furnace body, it could achieve efficient preparation of single crystal blades.

    • XU Yangtao, Wang Tangchao, LV Xin

      2023,52(11):3939-3946 DOI: 10.12442/j.issn.1002-185X.20220877

      Abstract:To investigate the effects of alloying Ta and Mo elements on the strength and morphology of the γ′ phase of Co-Al-W-based high-temperature alloys, the γ′-L12 supercell structure was constructed, doping calculations were performed at six nonequivalent sites, and the energy structure and mechanical properties were analyzed; and Co-8.8Al-9.8W-2X (X = Ta, Mo) alloys were prepared, and the alloys were deformed in 5% and 10% compression. The γ′ phase morphology and dislocation morphology of the alloy were analyzed using transmission electron microscopy (TEM) technique. The results show that the Ta atoms preferentially occupy the Al2 position and the Mo atoms preferentially occupy the W6 position during alloying, and the Ta atoms occupy the Al2 position, which increases the strength and tissue stability of the γ′-L12 doped structure, while the Mo atoms doping at the W6 position has the opposite effect. The γ′ phase shape can be maintained as cubic when the alloy is compressively deformed, and the dislocation damage to the γ′ phase is more limited, while the strength of the γ′ phase of the 2Mo alloy is reduced due to the preferential occupation of the Mo atoms in the W6 position, and the γ′ phase shape is changed from cubic to raft when the alloy is compressively deformed, and the dislocation damage to the γ′ phase is more serious.

    • >Materials Science
    • He Ronghui, Wang Han, Zhang Ze, Li Jingyuan, Wen Liangyuan

      2023,52(11):3697-3706 DOI: 10.12442/j.issn.1002-185X.20230192

      Abstract:In order to ameliorate the microstructure characteristics and degradation behavior of the medical Mg alloys, the extrusion process was conducted to change the grain size characteristics and the distribution law of secondary precipitates/intermetallic compounds, and the microstructure characteristics and degradation behavior of as-extruded Mg-2Zn-0.5Gd-1Y-0.5Mn Mg alloy were analyzed. Results show that different hot-extrusion deformation methods do not change the types of the secondary phases in Mg-2Zn-0.5Gd-1Y-0.5Mn Mg alloy, but change their distribution and morphology. The main components of Mg-2Zn-0.5Gd-1Y-0.5Mn Mg alloy are α-Mg and W-Mg3Y2Zn3 phases. The electrochemical tests demonstrate that the corrosion current densities are 2.498, 3.656, and 1.012 μA·cm-2 for as-cast, extruded/370 °C, and extruded/390 °C Mg alloys, respectively. The precipitates/intermetallic com-pounds of strip shape are distributed in the matrix of as-cast Mg alloy, which can act as the micro-cathode, thus forming the galvanic-corrosion sites and accelerating the corrosion rates. Partial coarse precipitates cannot completely dissolve into the α-Mg matrix due to the low actual temperature of the Mg alloy during extrusion at 370 °C. With the disordered distribution and the increasing precipitates, the area proportion of micro-cathode is increased, which accelerates the corrosion rate. However, for the Mg alloy during extrusion at 390 °C, the extrusion speed is fast, the dissipation behavior is slow, and the friction between ingot and extruder is intense, indicating the occurrence of sufficient dynamic recrystallization, which reduces the number/area of micro-cathode and improves the corrosion resistance.

    • Liu Guoqin, Lian Lixian, Liu Ying

      2023,52(11):3730-3735 DOI: 10.12442/j.issn.1002-185X.20230238

      Abstract:CeN powder was prepared through the carbothermal reduction nitridation reaction assisted by sol-gel method. Citric acid (CA) was used as the chelating agent, indicating that the organic material is used as the carbon source. The whole process could be divided into an aqueous phase process and a heat treatment process. The aqueous phase process mainly involved the chelation and polyester of Ce3+ and CA to form stable Ce3+-CA chelate precursors. Homogeneous mixing at the molecular level of Ce and C sources could be achieved by the aqueous phase process. The heat treatment process included the in-situ carbonization and carbothermal reduction nitridation reaction. The in-situ carbonization process formed CeO2/C powder, promoting the close contact between CeO2 and C. The diffusion distance between the atoms of Ce and C sources is reduced to facilitate the carbothermal reduction nitridation process.

    • Lu Doudou, Li Shan, Tang Kebin, Wang Liangtao, Chen Zheng

      2023,52(11):3736-3740 DOI: 10.12442/j.issn.1002-185X.20230236

      Abstract:To improve the hard and brittle mechanical characteristics of single crystal germanium (Ge), the molecular dynamics (MD) simulation was used to study the mechanism of surface modification on single crystal Ge by ion implantation with three different doses. Results show that the ion implantation causes amorphous phase damage to Ge matrix, and the nano-indentation process shows the lattice evolution. The nano-indentation results reveal that the existence of amorphous phase can reduce the hardness and brittleness of single crystal Ge and enhance its plasticity. Additionally, the degree of amorphous phase damage and the hardness of Ge matrix are related to the ion dose. With increasing the ion dose, the amorphous damage is deepened, and the hardness is decreased.

    • Zhao Kuan, Li Jinping, Wang Bangwen, Cui Qiang

      2023,52(11):3741-3747 DOI: 10.12442/j.issn.1002-185X.20230174

      Abstract:To explore the influence of randomness of materials and loads on the crack driving force of TP304 stainless steel, a probability prediction for crack driving force through the elastic-plastic finite element method (EPFEM) coupled with the Kriging surrogate model was proposed. To improve the efficiency of finite element analysis, MATLAB was used to further develop the pre-processing and post-processing procedures of ABAQUS software to realize the automatic change of random specimens, batch calculation, and automatic analysis of probability prediction results. The statistical distribution law of the crack driving force of TP304 stainless steel material under the action of random factors was obtained, as well as other probability characteristics, including failure probability, failure probability density function, cumulative probability density function, etc. The sensitivity of each random factor was analyzed. Finally, the effectiveness and efficiency of the proposed method were analyzed, compared with those of the Monte Carlo method. Results show that the randomness of load and material parameters can significantly influence the driving force of crack tips of TP304 stainless steel, thereby affecting the failure probability of TP304 stainless steel. The load and strain hardening exponent present the most obvious effect on the dispersion of crack driving force of austenitic TP304 stainless steel.

    • Zhang Yuhan, Jin Na, Liu Ying

      2023,52(11):3748-3756 DOI: 10.12442/j.issn.1002-185X.20230245

      Abstract:The first-principles calculation was used to investigate the influence of doping fourth-period transition metal elements on the structural, mechanical, and thermal properties of Mo2CoB2. Through the calculation of cohesive energy and formation enthalpy as well as the calculation comparison between the obtained results and Born-Huang criterion, all doped compounds are thermodynamically and mechanically stable. Point defect theory was employed to determine the occupation sites and occupation preference of doped elements in the Mo2CoB2 crystal cell. Results show that Sc and Ti exhibit strong preference for Mo sites, and V has a weak preference for Mo sites. Additionally, Cr, Mn, Fe, Cu, and Zn have a weak preference for Co sites, and Ni has a strong preference for Co sites. Debye temperatures were obtained by the contrast calculation. The results reveal that except Mo7TiCo4B8, Mo7VCo4B8, and Mo7CrCo4B8, the doped models all have lower Debye temperatures than the undoped model, suggesting that except Ti, V, and Cr elements, the addition of transition metal elements of large quantity into the Mo2CoB2 hard phase should be avoided. Furthermore, except that of the Cr-doped model, the hardness of the doped models is lower than that of the undoped model, and the models with doped elements at preferential sites normally exhibit higher hardness than those at non-preferred sites do. This research provides theoretical basis for the development of Mo2CoB2-Co cermet with improved properties.

    • >Materials Technology
    • LIU Jinsong, ZHANG Liangli, WANG Songwei, SONG Hongwu, ZHANG Shihong

      2023,52(11):3785-3793 DOI: 10.12442/j.issn.1002-185X.20220803

      Abstract:Horizontal continuous casting is a common method to produce copper strip. It is very important to explore the influence of process parameters on the quality of the billet. The influence of drawing speed on temperature field, liquid hole depth and cooling rate in mold was analyzed by numerical simulation, and the influence mechanism of drawing speed on the structure of billet was revealed by process test. The results show that with the continuous increase of the billet drawing speed, the depth of the liquid hole in the mold continues to increase, and the cooling rates of the surface and core of the billet along the traction direction gradually decrease, and the difference between the two cooling rates gradually decreases. When the drawing speed was 149mm/min, the cooling rates of the two parts reach the same. With the continuous increase of the billet drawing speed, the angle θ between the grain growth direction and the traction direction on the section of the billet increases gradually, the grain growth distance was shortened, the number of grains on the surface of the billet increases, and the average grain diameter decreases from 1.96mm to 1.05mm, and the overall microstructure uniformity was obviously improved.

    • Li Mingfei, Chen Wei

      2023,52(11):3794-3800 DOI: 10.12442/j.issn.1002-185X.20220806

      Abstract:Aimed at improving the performance and compactness of the heat pipe heat exchangers, different forms of double-pipe heat exchanger units with densely longitudinal fins are obtained by metal additive manufacturing method. The manufacturing deviation is summarized, which shows that the internal structure is complete. The optical measurement shows that the roughness distribution on both sides of the inclined fin is not uniform. The steady state experiments are implemented to investigate the heat transfer characteristics of four densely longitudinal fins enhanced compact double-pipe heat exchanger units. The configurations are classified into two categories of straight fin type (DPHE-1) and periodically arranged fin type (DPHE-2). Within the Re ranging from 2000 to 15000, the tested results show that, due to the increase of heat transfer area and the enhancement of flow mixing effect, the DPHE-2 gives 1.3~1.4 folds averaged Nusselt number and 12.6~28.6 averaged friction factor than the DPHE-1. Comparing their overall heat transfer performance, the long fin scheme in DPHE-1 type performs best.

    • 何龙军, Wang Qingyang

      2023,52(11):3801-3808 DOI: 10.12442/j.issn.1002-185X.20220824

      Abstract:Two 100-m MgB2 wires with different conductor structures (Cu core and CuNb core) were designed and successfully fabricated by the central Mg diffusion process (IMD), and the mechanical and transport superconductivity of the wires were tested. The uniformity of MgB2 superconducting layer distribution along the longitudinal direction of the two wires was analysed by different methods, and it was found that the distribution of superconducting layer tended to be more uniform as the diameter of the wire decreased, and the MgB2 FF fluctuation range of the wire with Φ 0.8 mm was the smallest, and the extreme difference of the base super ratio was 0.02. The results of the uniformity of MgB2 layer distribution showed that the Mg and B densities in the wire were well distributed. The results of the superconductivity tests show that the critical current Ic of the Cu replacement core wire is 19 A (4.2 K, 4 T) higher than the critical current Ic of the CuNb replacement core wire, while the Jc performance is basically the same. The Mg/B/Nb/Monel matrix composite enable to manufacture high performance MgB2 wires with 100-m class.

    • Zou Tianchun, Guan Yuxi

      2023,52(11):3818-3824 DOI: 10.12442/j.issn.1002-185X.20220830

      Abstract:Single-layer sandwich panels and six kinds of multilayer sandwich structures were prepared using closed-cell aluminum foam and aluminum alloy sheets. The cellular and macroscopic deformation modes were analyzed to study the influence mechanism of the plates and layer number on the quasi-static mechanical properties and energy absorption characteristics. The results show that the plates can adjust the stress state and make the cores collapse layer by layer, which reduces the multilayer synchronous deformation, lateral and bilateral slip caused by the formation and extension of the inclined deformation bands, so that the structure has higher collapse stress, platform stress, energy absorption per unit volume and smaller densification strain. The increase of the layer number leads to the increase of the length and number of the deformation bands in the structures without plate, thus changes the macroscopic deformation mode, results in the aggravation of the slip phenomenon on both sides, leads to the accumulation of cellular defects in the structures with plate, affects the stable deformation, results in the increase of densification strain, the reduction of collapse stress, platform stress and energy absorption per unit volume, and the decrease of energy absorption efficiency at densification strain. Compared with other structures, the three-layer structure with plates has the best compression resistance and energy absorption properties.

    • Qi Jinlei, Wang Longpeng, Han Dongya, Lin Jiangyuan, Huang Hao, Wen Mao

      2023,52(11):3825-3831 DOI: 10.12442/j.issn.1002-185X.20220832

      Abstract:In this paper, a series of Ni3Al films were successfully prepared by magnetron sputtering at different bias voltage, and then the bias voltage-dependent composition, deposition rate, microstructure, hardness and fracture toughness were studied in detail by XPS, XRD, SEM, AFM, nanoindentation and digital microhardness tester. The results showed that introducing the bias voltage could increase the kinetic energy of the ionized charged ions during sputtering, thus significantly improve the deposition rate, the density of the internal structure and the surface smoothness of Ni3Al films; In addition, the introduction of appropriate bias voltage could induce the formation of amorphous/nanocrystalline composite structure to improve the crystallinity of the films. The wrapped nanocrystalline composite with biphasic structure could provide a large number of grain boundaries, which strengthen the blocking effect on dislocations, leading to the dislocation stacking at the grain boundary and resulting in the increasement of hardness. Meanwhile, the existence of the large number of grain boundaries could also consume the energy of crack propagation to inhibit the generation of macrocracks, and significantly enhance the fracture toughness of Ni3Al films.

    • shukanghao, xiongyi, liyong, zhangxin, yinlitao, ren fengzhang

      2023,52(11):3832-3840 DOI: 10.12442/j.issn.1002-185X.20220846

      Abstract:Novel Ni-W-Co-Ta heavy alloys were cold rolled under room temperatures to characterize the microstructural evolution and mechanical properties by using optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffractometry, electron back scattered diffraction, tensile testing and microhardness testing. The results show that equiaxial grains were elongated along the rolling direction and a fibrous texture could be observed with an increase in deformation, in which a large number of slip bands were generated to coordinate the intensive plastic deformation. The sharp increase in dislocation density significantly promoted the dislocation interaction, which, in turn, refined the grain size down to 25.2 nm. After 90% severe plastic deformation, the tensile strength is increased to 1953 MPa. The yield strength is increased to 1806 MPa, the hardness is increased to 534 HV, and the elongation is sharply decreased by 9.1%. The fracture morphology changed from a typical ductile fracture to quasi-cleavage and ductile mixed fractures.

    • Song Shuanjun, Qiu Chenghong, Han Yuqi, Fang Zeyu

      2023,52(11):3841-3846 DOI: 10.12442/j.issn.1002-185X.20220833

      Abstract:Laser filamentous wire additive manufacturing technology is a manufacturing technology that can rapidly form small parts. However, due to the influence of thermal accumulation effect in the manufacturing process, it is often unable to ensure the precision shape control of formed parts. In order to solve this problem, this paper uses the calibrated infrared thermography to collect the surface temperature of single pass multi-layer thin-walled parts, and studies the characteristic variation law of temperature field and heat accumulation effect in the manufacturing process, which provides a basis for the optimization of forming process. The results show that the infrared thermal thermography can be used to study the evolution of temperature field in the process of thin wall stacking. With the increase of cladding height, the area of high temperature area gradually increases, and the heat accumulation effect is significantly enhanced. In the process of cladding, the heat is conducted downward, the heat dissipation condition becomes worse gradually, and the cooling rate of each layer decreases with the increase of the number of layers until it becomes stable. In addition, when the number of cladding layers is more than 15, the thermal accumulation effect will no longer affect the cladding layers below 15.

    • Ren Lei, Fu Guangyan, Liu Enze, Tan Zheng, Ning Likui, Lai Yongjun, Tong Jian, Li Haiying, Zheng Zhi

      2023,52(11):3857-3866 DOI: 10.12442/j.issn.1002-185X.20220838

      Abstract:The oxidation behaviors of new-type Fe-Ni-Cr-Al alloys with different Y contents in air atmosphere at 1300 ℃ were studied by isothermal oxidation test. The type and distribution of oxidation products were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that the addition of Y element is beneficial to the oxidation resistance of Fe-Ni-Cr-Al alloy. The reason is that the Y element can promote the formation of a dense composite protective layer of spinel and chromium oxide on the surface of Fe-Ni-Cr-Al alloy, and then slow down the diffusion of the elements in the matrix. At the same time, Y element can accelerate the transformation mode of Al2O3 from internal oxidation to external oxidation and slow down the internal nitridation process. In summary, the oxidation resistance increases.

    • Yu Lianqing, Liu Ke, Zhang Yaping, Zhu Haifeng

      2023,52(11):3867-3872 DOI: 10.12442/j.issn.1002-185X.20220841

      Abstract:Effects of disproportionation time and dehydrogenation pressure on the magnetic properties and anisotropy of HDDR magnetic powders were studied. The phase structures of the samples were identified by X-ray powder diffraction. The microstructure was investigated using scanning electron microscope. The magnetic properties of NdFeB were measured by AMT-4A magnetic measuring instrument. The results showed that the disproportionation time determines the content of the disproportionated phase and the residual parentNd2Fe14BH1.04 phase in the material after the HD process. The residual parent Nd2Fe14BH1.04 can inherit the texture information of the original Nd2Fe14B phase, which results in strong c-axis texture of new phase Nd2Fe14B. When the disproportionation time extends to 40 min, the anisotropy of the magnetic powder reaches the maximum, DOA=0.55. The dehydrogenation pressure mainly acts as the driving force for the crystal growth. The low pressure of 0.01 Mpa will cause over large driving force, which leads to the weak anisotropy of the generated new phase Nd2Fe14B. The magnetic powder has the optimum anisotropy when the dehydrogenation pressure is at 0.03 Mpa, DOA=0.53.

    • WANG Xie, LEI Qian, LIU Yong

      2023,52(11):3893-3899 DOI: 10.12442/j.issn.1002-185X.20220854

      Abstract:A Cu-Sn-Fe-Ni alloy was prepared by melt casting and thermomechanical treatment The static corrosion behavior in NaCl solution was characterized by scanning electron microscope and X-ray photoelectron spectroscopy. Finally, the corrosion mechanism of the alloy was discussed and analyzed. The results show that the static corrosion rate of the alloy in 3.5 wt.% NaCl solution is 0.0473 mm/a, and the corrosion resistance is good; The corrosion resistance of the alloy increases first and then decreases with the increase of immersion time; The alloy has an obvious preferential corrosion tendency in the immersion process. At first, Fe removal corrosion occurs, and then Cu oxidizes to form a relatively dense passivation film, which reduces the corrosion rate of the alloy. Later, Sn and Ni begin to dissolve and corrosion, forming an oxide film, which makes the passivation film denser. However, at the time, Fe removal corrosion still occurs in the lower layer of the passivation film, which promotes the local destruction of the dense passivation film, leading to the decline of the corrosion resistance of the alloy.

    • Sun Jifeng, Ke Liming, Xu Yang

      2023,52(11):3900-3908 DOI: 10.12442/j.issn.1002-185X.20220861

      Abstract:For Al/Mg friction stir welded (FSW) joints, when the thickness of base metal is too large, thicker brittle and hard intermetallic compounds (IMCs) are easily formed along the interface, which makes joint formation extremely difficult. In this paper, the interface interlocking composite Zn interlayer is innovatively used to study the evolution of IMCs at the interface of thick plate Al/Mg FSW joint and the change rule of joint performance, which provides theoretical and practical basis for subsequent high-strength joining of Al/Mg FSW joints. The results show that a low melting point eutectic layer (Mg+ Al12Mg17) with an average thickness of 69.7μm is formed at the upper part of the magnesium side interface of the oblique butt joint, and IMCs with an average thickness of 42.7μm and 21.2μm are formed at the middle and lower part. The IMCs layer consists of Al12Mg17 and Al3Mg2。Compared with oblique butt joints, when interfacial interlocking compound Zn interlayer is used, Al-Mg-Zn phase (Al5Mg11Zn4) and Mg-Zn phase (MgZn2, Mg2Zn3) are generated locally at the interface, replacing the original Al-Mg IMCs with a minimum IMCs thickness of 3.9μm. The tensile strength of the joint is increased from 2.7MPa of oblique butt joint to 32.3MPa of interfacial interlocking composite Zn interlayer joint, which is related to interfacial interlocking effect and thickness reduction of IMCs.

    • Li Weiguang, Xiao Pan, Lu Zhonghui, Li Yingzhi, Xia Yongsheng, Chu Yingjun, Pan Jilin

      2023,52(11):3915-3921 DOI: 10.12442/j.issn.1002-185X.20220870

      Abstract:The corrosion behavior of copper pipes buried in tropical rain forest soil environment for a long time was studied by weight-loss method, morphology analysis, composition analysis and electrochemical test in this paper. The results show that the average corrosion rate of the copper pipe after 16 years of burial is 2.5 μm/y, the law of corrosion weight loss conforms to the power function model, and its fitting equation is C=0.4273t-0.246. The corrosion products on the surface of the copper tube show a light green dense scale structure, which is well combined with the metal matrix. XPS、EDS and FTIR analysis results show that the main component of the corrosion product is copper green (Cu2 (OH) 2CO3). The electrical test results show that after 16 years of burial, the corrosion rate of the copper tube decreases and the impedance value increases significantly, indicating that the corrosion product film has a good protective effect on the substrate and can effectively slow down the continuous development of the corrosion process.

    • chenwenlian, yangyihang, chenxiaohong, zhengjunjie, gusiyong, zhanghouan

      2023,52(11):3922-3930 DOI: 10.12442/j.issn.1002-185X.20220871

      Abstract:The selective laser melting (SLM) 3D printing method was applied to design and manufacture tungsten materials with lattice structures. The changes in the mechanical properties of tungsten materials under different lattice structures were investigated through finite element analysis, scanning electron microscopy, and quasi-static uniaxial compression tests. The influence of microstructure on mechanical properties was analyzed.The results indicate that the ARC lattice structure can effectively reduce stress concentration at the nodes, while maintaining the lightweight and low porosity characteristics of the lattice structure, as well as the high-strength mechanical properties of tungsten materials. The average compressive strength reaches 535MPa, while the average mass is only 1.25g. After laser printing, the ARC lattice has an average compressive strength increase of 93% compared to the cubic lattice, with the Body-Centered arc lattice (BCA) showing superior compressive performance, reaching a maximum compressive strength of 721MPa, and a theoretical structural density of 12.8%. The mechanical performance of 3D printed W is close to plastic processed sample. Compared with the cubic lattice, the arc lattice has good ability absorption characteristics, and the total energy absorption value of the latter is increased by 223% compared with the former, and the average energy absorption of the arc lattice reaches 1664J/cm3. In addition, the SEM image shows that the arc lattice reduces the hanging distance of the oblique pillar in the printing due to its arc characteristics, and the forming effect is better than that of the cubic lattice.

    • Zhu Lixian, hejunjie, Zhang Renyin, Fu Li, Zhou Xuan, Mao Yong

      2023,52(11):3931-3938 DOI: 10.12442/j.issn.1002-185X.20220875

      Abstract:Platinum iridium bonding wire is a high-strength wire bonding material used in the packaging of special microelectronic devices, and heat treatment is the key method for the cold-deformed platinum-iridium alloy microfilament to control the lifetime service performance of the bonding wire. Based on the Φ25 μm Pt-10Ir ultrafine bonding wire, the microstructure and deformation of ultrafine filaments under different annealing processes were analyzed and measured by high-resolution FIB-EBSD linkage characterization technology, and the evolution of their mechanical and electrical properties was statistically studied. The results show that with the increase of annealing temperature, the microstructure gradually changes from fine fibrous grains to partial equiaxed grains. The equiaxed grains preferentially grow at the grain boundary. Simultaneously, the intensity of the silk texture gradually decreases, the breaking force gradually decreases, the elongation gradually increases, and the resistivity shows a trend of first decreasing and then increasing. After the annealing of Pt-10Ir ultra-fine bonding wire at 600°C/30 min, recovery rather than recrystallization occurs in the microstructure, the texture orientation evolves into a deformation texture parallel to the wire drawing direction of <111> with a breaking force of 37.06 cN, a tensile strength of 755.29 MPa, an elongation of 1.30%, and a resistivity of 22.81 μΩ·cm, showing an excellent mechanical/electricity comprehensive performance. This study will provide a theoretical and experimental basis for the optimization of microstructures and properties in high-strength precious metal ultra-fine bonded wire.

    • zhang zhi ying, liang rui qing, chen jun lin, mei chao yuan, li juan, sun run guang

      2023,52(11):3947-3953 DOI: 10.12442/j.issn.1002-185X.20230384

      Abstract:The surface of nanodent and nanopore structured alumina membranes with different periods were directly modified by Angelica sinensis polysaccharide (ASP) or covalently modified by ASP via γ-aminopropyl triethoxysilane (KH550). After that, the morphology and cell viability of breast cancer cells MDA-MB-231 grew on the modified nanostructured surfaces were systematically studied. It was found that nanodent and nanopore structure directly modified by ASP could effectively inhibit the viability of breast cancer cells, and had little effect on cell morphology. However, the inhibitory effect of nanodent structure on cell viability was superior to that of nanopore structure. Nanodent structure with period of 300 nm had the best inhibitory effect on cell viability, and the inhibitory rate is 27.7%. The nanodent and nanopore structures covalently modified by ASP via KH550 had a better inhibitory effect on cell viability than that directly modified ASP, and the cell morphology changed obviously. A large number of lamellipodia were generated around the cell body. However, the inhibition effect of the nanodent structure on cell viability was better than that of the nanopore structure. Nanodent structure with period of 300 nm had the best inhibitory effect, and the inhibition rate is 28.2%. These results have a certain function for the design and delivery of drugs.

    • >Reviews
    • Wang Yichang, Yuan Lingyang, Yang Lei, Peng Liming, Ding Wenjiang

      2023,52(11):3954-3970 DOI: 10.12442/j.issn.1002-185X.20220800

      Abstract:Aluminum alloy castings exhibit versatile prospects in critical aircraft, aerospace, and lightweight of automobile owing to their ultralow density and excellent specific strength. The optimization of forming and mechanical properties of cast Al alloys can significantly expand their applications. In this work, the research progress of Al-Zn high strength cast aluminum alloy are reviewed. The strengthening mechanism and research results on (micro-)alloying, grain refinement, structure purification, and heat treatment optimization of high-strength as-cast aluminum alloys are summarized. The existing problems are also discussed. At last, the development trends of as-cast aluminum alloys with high strength and toughness were prospected, which has certain practical and theoretical significance for the aluminum alloys.

    • Yuan Kunquan

      2023,52(11):3981-4001 DOI: 10.12442/j.issn.1002-185X.20220804

      Abstract:High-entropy alloys based on the multiple components design concept exhibit excellent comprehensive properties such as high strength, high toughness, good wear resistance, oxidation resistance and thermal stability, making it prospective to become an excellent new structural material. As for the composition design, high-entropy alloys can adjust its stacking fault energy and microstructure by changing the concentration of each principal element, doping interstitial atoms and so on, and then introduce multiple strengthening and toughening mechanisms such as precipitation strengthening, fine grain strengthening, phase transformation or twinning-induced plasticity effect, thereby improving its comprehensive mechanical properties. In this paper, the effects of composition design with non-equiatomic and interstitial C/N atom additions on the microstructure, mechanical properties and deformation mechanism of face-centered cubic high-entropy alloys are summarized, so as to provide the theoretical basis for the design of the new high-performance face-centered cubic high entropy alloys.

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    • li leyu, tian fuzheng, li zheng, zhang jingang, deng zhiwei, chen xing, liu xinling

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230618

      Abstract:In this paper, we investigated the fatigue crack propagation behavior of DD6 nickel-based single-crystal superalloy at test temperatures ranging from 530℃ to 850℃. The fatigue properties were assessed along the [001] direction, parallel to the loading axis in tension. Following the fatigue crack propagation test, the fracture morphology was examined using scanning electron microscopy for classification into one of four zones. These were based on specific morphology characteristics and were as follows: source zone, prefabricated crack zone, stable extension zone, and rapid extension zone. Electron backscatter diffraction was utilized to observe the profiles of plastic deformation perpendicular to the fracture. Additionally, the dislocation process near the fracture was studied using transmission electron microscopy. Our findings show that oxidation occurs at 650℃ under conditions influenced by the temperature field, stress field, and exposure time, and that the γ" phase is also weakened. Furthermore, a significant number of consecutive dislocations form in the γ and γ" phases between 650℃ and 760℃, resulting in increased alloy oxidation and a notable decrease in fatigue resistance and product lifespan..

    • Zhu Wei, Cheng Dazhao, Liu Caiyan, Ma Cong, Wu lu, Zhang Jing

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230621

      Abstract:The austenite Fe-Cr steels used as the critical in-pile components because of its good high temperature resistance, corrosion resistance and excellent mechanical properties and thermal strength, bear long-period high temperatures and irradiation; the irradiated vacancies aggregate into voids leading to irradiation swelling and hardening, which seriously affects the service safety of the reactor. The phase field method coupling temperature field is employed by solving the phase field equations based the Fourier spectrum method to investigate the voids behavior of austenite Fe-Cr steels upon a central and a one-dimensional temperature field. As the temperature goes down from the center radically in a central temperature field, the vacancies diffuse toward the high-temperature center region driven by the temperature gradient, resulting in the instability of the double voids model, and gradually dissolves to form a new void in the high temperature center region. In the central temperature field, the voids nucleate earlier and grow faster with a sizeable scale in the high temperature than that in the lower temperature region due to the higher vacancy concentration in the central high temperature region. Based on the force-flow relation in the principle of irreversible thermodynamics, the migration behavior of voids upon a one-dimensional temperature gradient is studied by adding advection term to the phase field evolution equation Cahn-Hilliard equation. It has been observed in the experiments that the size of voids in irradiated austenite Fe-Cr steel is nanoscale, and it is generally believed that the nanoscale voids migration is controlled by the bulk diffusion mechanism and surface diffusion mechanism. Therefore, the effects of temperature gradient and initial size of voids on the voids migration upon a one-dimensional temperature gradient in austenite Fe-Cr steel are studied considering both the bulk diffusion mechanism and surface diffusion mechanism respectively. The migration rate governed by the bulk diffusion mechanism positively depends on the temperature gradients but not the initial void"s size. The migration rate governed by the surface diffusion mechanism positively depends on the temperature gradients but is negatively related to the initial void"s size. At the same time, in the process of migration, the shape of the void will also change, and the void will be elongated along the direction of temperature gradient, and the front end is sharper along the direction of temperature gradient, and the back end is wider. The studies inspire the microstructure aging and properties prediction caused by inhomogeneous heat conduct or macroscopic uneven temperature distribution.

    • Wang Yao, Li Jinshan, Chen Bo, Chen Mingju, Chen Biao, Wang Yi, Gong Weijia

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230625

      Abstract:Accident-tolerant fuel can significantly enhance the capability of light-water nuclear reactors to withstand core melting under LOCA, is a revolutionary development of nuclear fuel technology and nuclear power safety. Cr-coating deposited on the current Zr-based nuclear fuel cladding demonstrates good adhesion, excellent corrosion resistance in high-temperature and high pressure water, and high-temperature oxidation resistance. Therefore, Cr-coated zirconium alloys emerge as the most promising ATF solution for practical engineering application in nearest future. The present paper reviews the research progress on oxidation behavior of Cr-coated zirconium alloy in high-temperature steam environment. The oxidation kinetics of the Cr coating, the effect of microstructure on the anti-oxidation performance of the Cr coating, the failure mechanism of the Cr coating after long-term oxidation and the Cr-Zr interdiffusion behavior are discussed. Additionally, strategies for enhancing the anti-oxidation performance of the Cr coating and suppressing Cr-Zr interdiffusion are summarized, and future development directions are prospected, aiming to provide references for the optimization design and engineering application of Cr-coated Zr-based nuclear fuel cladding.

    • Zhao Yanchun, Song Haizhuan, Ma Huwen, Hu Ruonan, Feng li, Duan Wangchun, Peter K Liaw

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230636

      Abstract:In this study, (Fe63.3Mn14Si9.1Cr9.8C3.8)99.5-xCuxAg0.5 (x=1, 2, 3, 4, 5 at.%) alloys were prepared using a water-cooled copper crucible magnetic levitation vacuum melting furnace. The effects of different Cu contents on microstructure, the corrosion resistance and antibacterial performance of the alloys were investigated. The results showed that the medium entropy alloys possessed FCC phase after solid solution and aging treatment. With the increase of Cu content, the FCC2 Cu-Ag riched phase precipitated on the FCC1 Fe riched matrix. The corrosion resistance of the alloys in a 3.5% NaCl solution was superior to AISI304. And the corrosion current density first decreased and then increased, and the impedance arc radius first increased and then decreased, indicating an initial enhancement and subsequent weakening of the corrosion resistance as the Cu element adding. Moreover, the corrosion rate of the alloys in Escherichia coli suspension shows a trend of first increasing and then decreasing. Among them, the x=2 alloy exhibited the best corrosion resistance. And there is a trade-off effect between the corrosion resistance and antibacterial performance. The FCC2 phase effectively enhances the antibacterial performance of the alloy, whereas the antibacterial rate of the x=5 alloy reaches 99.93%.

    • Niu Yong, Jia Yunjie, WANG Yaoqi, Zhu Yanchun, Zhang Zongyuan

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230646

      Abstract:In this study, the deformation mechanism of single-crystal titanium was investigated by molecular dynamics simulation, the temperature was 500~1000K, the strain rate was "0.0001" 〖"ps" 〗^"-1" ~"0.01" 〖"ps" 〗^"-1" , and the loading mode was tensile and compressive, and the results were subjected to the stress-strain analysis, potential analysis, coevolutionary neighbourhood analysis and dislocation density analysis. The results show that with the increase of temperature, the yield strength decreases, and the strain value corresponding to the yield point decreases; at the same temperature, the tensile yield strength is slightly higher than the compressive yield strength; the modulus of elasticity does not change much under different loading rates, and the yield strength increases with the increase of loading rate. With the increase of temperature or loading rate, the peak potential energy of the system increases. As the strain proceeds, the HCP structure decreases, the Other structure increases, and the BCC and FCC structures appear and increase (except at the deformation temperature of 1000K); after exceeding the yield point, the various structures gradually tend to stabilise; with the increase of temperature, the transformation of crystal structure occurs earlier. The dislocation density decreases with increasing temperature, and the total dislocation density under tensile load is larger than that under compressive load; The main types of dislocations throughout the deformation process are Other dislocations, 1/3<-1100>dislocations and 1/3<11-20> dislocations.

    • Shang Xiaofeng, Sun Chen, Zhao Yuhui, He Chen, Zhao Jibin

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.20230667

      Abstract:Objective To solve the connection problem of TC4-7075 heteroalloy with large differences in physical parameters, and to expand the application range of high specific strength titanium-aluminum heteroalloy composite structure. Methods AlTiVNbSi high-entropy alloy was selected as the intermediate layer material, and the effective connection of TC4 and AA7075 heteroalloys was realized by laser melting deposition technology, and the macromorphology, microstructure, component distribution and interface characteristics of the junction area were characterized by metallographic microscopy (OM), scanning electron microscopy (SEM, EBSD), microhardness and tensile experiment. Results The connection joint is well combined with the TC4 titanium alloy side interface, and there is an interface transition zone with a width of about 20μm, TC4 near the interface has bundled Weisler tissue, and a compound area with a width of 20μm exists at the 7075 side interface. Conclusion Based on AlTiVNbSi as the intermediate layer material of high-entropy alloy, laser melting deposition technology can realize the effective connection of titanium-aluminum heteroalloy, the hardness of the joint is about 696HV, which is higher than the hardness of the base metal, the hardness of the connecting zone on the near titanium side is higher than that of the connecting zone on the aluminum side, and the tensile strength is 116MPa.

    • MA Xiang-long, CAO Rui, DONG Hao, WANG Tie-jun, YAN Ying-jie

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.E20230024

      Abstract:The present study conducted hot isostatic pressure diffusion bonding experiments on TC4 titanium alloy and Al6061 aluminum alloy. The interface characteristics, formation mechanism, and mechanical properties of the TC4/Al6061 joint were investigated, and the relevant experimental phenomena were explained by thermodynamic analysis. The results indicate that the mutual diffusion of elements occurs after hot isostatic pressure diffusion bonding and subsequent annealing treatment. The chemical potential driving force leads to the enrichment of Si and Mg in the reaction layer, while Al is enriched on the other side of the reaction layer. The intermetallic compounds, including TiAl3, TiAl, and Ti3Al at the joint interface are formed through metallurgical reactions. The model for effective heat formation indicates that the preferential formation of the TiAl3 phase has occurred. The hardness test indicates that the Ti-Al intermetallic compounds formed at the interface exhibit higher levels of hardness. The tensile test reveals that the joint attains a maximum tensile strength of 144MPa.

    • Li Huizhao, Liang Kaiming, Pan Rui, Wang Caimei, Zhu Xiaoteng, Hu Zhenggen, Zhang Hua

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.E20230026

      Abstract:This research study employed self-designed induction coils, rigid restraint kits, and the existing laboratory induction heating apparatus to conduct a local induction heating-based rigid restraint thermal self-compressing bonding (TSCB) treatment on a 5 mm-thick TC4 titanium alloy plate (the base metal). The objective was to investigate the influence of holding temperature and heat treatment on the microstructure and mechanical properties of the joint. The results demonstrate that excessively low holding temperatures (900°C) result in insufficient atomic diffusion, while excessively high holding temperatures (990°C) exceeding the β to α phase transformation temperature lead to the formation of coarse widmanstatten microstructures, both of which contribute to a decrease in the mechanical properties of the joint. As the temperature increases, the pressure applied to the joint by the thermal constraint stress field initially rises and subsequently declines, accompanied by a corresponding trend in the quality of the joint connection. Optimal mechanical properties were achieved only when the holding temperature was slightly below the β to α phase transformation temperature, specifically at 950°C. At this temperature, the microstructure distribution exhibited the highest level of uniformity, characterized by a significant presence of equiaxed α-phase grains. Additionally, the atomic diffusion was sufficiently enhanced, coupled with the highest pressure exerted on the joint by the stress field, resulting in the attainment of optimal mechanical performance. Upon annealing heat treatment at 650℃/3h, the α→β phase transformation was observed, accompanied by a reduction in the degree of lattice distortion and grain refinement. The residual stress state of the TSCB joint was transitioned from tensile stress to compressive stress. The residual stress was significantly reduced, leading to stress relief. Consequently, the mechanical properties of the TSCB joint were improved, addressing the issue of low plasticity in the TSCB joint.

    • wang huigai, zhang keke, wang bingying, wang yaoli

      Available online:December 01, 2023  DOI: 10.12442/j.issn.1002-185X.E20230029

      Abstract:Sn2.5Ag0.7Cu0.1RE0.05Ni lead-free solder alloy taken as the research object and Ni-modified GNSs (Ni-GNSs) as the reinforcement phase, Ni-GNSs reinforced Sn2.5Ag0.7Cu0.1RE composite solder was made using mechanical alloying. The soldering test of composite solder/Cu and the thermal aging test of soldering joints were carried out to investigate the effect of Ni-GNSs on the microstructure and thermal aging fracture mechanism of composite soldering joints. The results showed that addition of Ni-GNSs inhibited the linear expansion of the composite solder, resulting in lattice distortion and dislocation. The intermetallic compounds (IMC) particles near the dislocation line interacted with the dislocation and hindered its movement, then the composite solder was strengthened. Druing the thermal aging process of this study, the thickness of interfacial IMC layer increased and the shear strength of soldering joints decreased. Among them, the shear strength of the composite soldering joints with 0.05wt.% GNSs addition decreased the least, only 8.9%. Moreover, after 384 h of thermal aging, its shear strength was still higher than that of the Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu soldering joints before aging. With the addition of Ni-GNSs, the growth coefficient of interfacial IMC of composite soldering joints was significantly reduced, which effectively alleviated the decrease of mechanical properties of composite soldering joints during the thermal aging process, and then changed the thermal aging fracture mechanism of composite solder/Cu soldering joints, and ultimately affected the reliability of joints. The fracture position of the Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu soldering joints moved from the soldering seam before thermal aging to the soldering seam/interfacial IMC, which was ductile-brittle mixed fracture. The fracture position of the Sn2.5Ag0.7Cu0.1RE0.05Ni-0.05GNSs/Cu soldering joints was all in the soldering seam zone, which was ductile fracture and the reliability of the joints was high.

    • LU Guoxin, LUO Xuekun, WANG Qiang, LIU Jide, WANG Xin, ZHANG Yongkang, LI Jinguo, LU Feng

      Available online:November 28, 2023  DOI: 10.12442/j.issn.1002-185X.20230616

      Abstract:With the further improvement of material fatigue life extension and processing of parts with complex shapes, laser shock processing has encountered more and more obstacles in practical applications and it is particularly urgent to improve and optimize the specific processing methods in laser shock treatments. Using the stress effect produced by pulsed lasers to process materials in various fields still has broad prospects. Given the specific needs of laser shock in different industrial applications, several processing improvement methods which get rid of the equipment dependence on high-performance laser units were proposed. The non-laser parameters referred to include adjustable indicators such as the absorption layer, constraint layer, and defocusing state between laser and material. The selected material, thickness, and other related attributes of the absorption layer and the constraint layer directly affect the intensity of laser-induced shock waves, while changes in defocusing amount lead to differences in physical or chemical effects on the material surface. The process setting range for the above non-laser indicators is wide and easy to control, and reflects good adaptability of irregular components. The development of new technologies for equal (unequal)-strength and high-strength surface strengthening based on changes in these indicators, as well as new green packaging technologies such as laser marking, are introduced in detail. The new ideas behind these new methods are expected to inspire researchers to further explore the application potential of green lasers.

    • zhangwei, chengdazhao, liucaiyan, macong, wulu, zhangjing

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230525

      Abstract:Nuclear materials are exposed to high temperature, high pressure and strong irradiation for a long time, and are subjected to strong neutron irradiation, which will produce a large number of point defects under the action of cascade collision, and then form radiation voids. Irradiation swelling caused by irradiation voids is responsible for the failure of austenite steel serve in the reactor core. The external stress introduced in the process of material processing and service and the elastic stress field generated by crystal defects such as dislocation have an important influence on diffusion and phase transformation. The phase field method at mesoscale can not only couple the physical fields such as temperature, irradiation and stress, but also simulate the dynamics and morphology evolution of the microstructure of materials during irradiation. A mesoscale phase field model coupled with rate and micro-elastic theory is used to survey the stress effects on void microstructures for Fe-Cr austenite; the global applied stress and the local dislocation stress field are considered. The applied stress promotes vacancies aggregate, nucleate, and growth, and the voids evolve into fusiform eventually. Voids in the stressed state have a larger size and lower density compared with a stress-free state. The larger the applied stress, the larger the average size and volume fraction, the smaller the number, and the more significant the morphology reconstruction is. The local elastic stress field of dislocation absorbs vacancies to reduce the elastic energy, and the concentrated vacancies accelerate the voids preferentially nucleate and grow around the dislocation. Compared with the dislocation-free system, the voids are fine and denser when dislocations exist; but the volume fraction and the morphologies of voids persist. In contrast, the applied stress should probably cause server swelling than dislocations in Fe-Cr alloys. The studying benefits the properties evaluation of in-core reactor components.

    • Wang Rongshan, Jia Xingna, Zhou Qian, Zhang Yanwei, Bai Guanghai, Xu Chi, Xue Wenbin

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230531

      Abstract:Zirconium alloys are used as fuel cladding materials in commercial reactors, which suffer from synergetic effects of irradiation and corrosion degradations. In order to evaluate the effects of irradiation on the corrosion behavior of the Zr-1Nb alloy, the alloy has been irradiated with 6.37 MeV Xe ions. The pre- and post-irradiation corrosion property modifications have been evaluated. The current paper have also reported the micro-hardness, surface roughness and phase composition modifications. After the Xe ion irradiation, unraveling surface has been observed due to the ion sputtering effect. The surface roughness and the microhardness are increased with increasing irradiation dose. The post-irradiation corrosion under LiOH solution result with lath shaped surface microstructures on the Zr-1Nb samples, which become more pronounced at higher irradiation doses. The polarization current density for the 0.5 dpa dose irradiated sample is increased by 18 times over that of the unirradiated sample, while it is about 72 times for the 2.7 dpa irradiated sample. After the ion irradiation tests, the polarization potentials are lowered (increased negatively) and the polarization resistance values are increased, compared with the unirradiated sample. The electro-chemical impedance spectra (EIS) results show that, the lower-frequency impedance values are decreased, the curvature radius of the capacitance curve is decreased and the phase angle peak is moving rightward with increasing irradiation doses. The polarization curves and the EIS results show that the ion-irradiation has increased the corrosion tendency of the Zr-1Nb alloy, and its corrosion resistance is decreased with increasing irradiation doses. The reduced corrosion resistance after the ion irradiation tests are considered to be mainly caused by the irradiation induced damages on the alloy matrix material.

    • He miaoxia, Yan Chi, Dong Yuecheng, Chang Hui, Alexandrov I.V

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230547

      Abstract:The effects of Mn microalloying on the microstructure and mechanical properties of a new near-α Ti-Al-Mo-Zr-Fe-B alloy were studied by OM, EBSD and TEM. The results indicated that the addition of 0.5wt.%Mn element can refine the casting microstructure of the alloy from 3.28μm to 2.65μm, which led to the tensile strength increase from 882MPa to 966MPa, however, the elongation to failure decreased from 7.8% to 5.1%. After forging, the grain size of two alloys tended to be similar, but the microstructure is more equiaxed and homogenious with the Mn microalloying. Compared with the tensile strength and elongation to failure of Ti-Al-Mo-Zr-Fe-B alloy increased to 966MPa and 16.4%, the alloy containing 0.5wt.% Mn element possessed higher tensile strength to 1079MPa, meanwhile, the elongation to failure retained to 15.7%. The increase of strength can be attributed to the solid solution strengthening effect of Mn element. At the same time, the Mn microalloying enriched the Al element to the α phase in the alloy, which is beneficial to improve the strength and plasticity of the alloy.

    • Shi Qianshuang, Bai Run, Hua Xingjiang, Li Shilei, Hu Boliang, Zhang Wen, Hu Ping

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230551

      Abstract:Low-density niobium alloys have characteristics such as low density, high melting point, and good corrosion resistance, and are widely used in aerospace, nuclear engineering, high-temperature structures, and other fields. To study the effect of different deformation processes on the microstructure and properties of low-density niobium alloys, rolling and extrusion deformations were carried out on the low-density niobium alloys in this study, and the effects were investigated through OM, SEM observation, mechanical property testing, and other methods. The results indicate that when rolling deformation is used, the deformation is large, the microstructure is uniform, the second phase is dispersed, the strength is high, and the plasticity is good, with an elongation after fracture of up to 37 %. When extrusion deformation is used, stress concentration can easily lead to cracking, and deformation is not easy to penetrate. The microstructure is not uniform, and the strength is high, but the plasticity is only 15 %, the impact of deformed microstructure on mechanical properties has been analyzed, which can guide the processing of niobium alloys.

    • XU Hanyuan, HUANG Taiwen, AI Cheng, MIAO Linkun, ZHANG Jun, LIU Lin

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230568

      Abstract:With outstanding comprehensive performance at high temperature, Nickel-based single crystal superalloy is the preferred material for aero-engine turbine blades, vanes and other components to withstand challenging service environment subjected to high temperature and intense stress. At present, various complex cooling structures are often used in the design of high-efficiency cooling blades to enhance blade temperature tolerance, among which the micro-cooling structure represented by lamilloy and double wall cooling are the main trend. However, the existence of ultra-thin wall structures in these complex turbine blades has become critical aspect and challenge in blade manufacturing. This paper provided an overview of the development trends in thin-walled structure of Ni-based single-crystal superalloys, analyzed the defects arising from thin-walled constrained space and the law of dendrite growth, elaborated the influence of thin-walled structure on mechanical properties and provided a prospect on advanced turbine blades preparation and development trend of its microstructure regulation.

    • Feng Li, Wang Zhipeng, Zhao Yanchun, Bian Chunhua

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230570

      Abstract:In this study, FeCrMnxAlCu (x = 0, 0.5, 1.0, 1.5, 2.0) high-entropy alloys were prepared using a vacuum arc melting furnace. The microstructure and chemical composition of the alloys were analyzed using equipment such as XRD, SEM, and EDS. Additionally, the corrosion resistance of the alloys in 3.5 wt.% NaCl solution was evaluated through electrochemical polarization curve tests and immersion experiments. After corrosion, the alloy surfaces were analyzed using XPS equipment.The results of microstructure characterization showed that the prepared high-entropy alloys exhibited typical dendritic and interdendritic structures and possessed a dual-phase structure of FCC and BCC . Corrosion test results indicated that the corrosion resistance of the high-entropy alloys increased initially and then decreased with an increase in Mn content. However, compared to the alloy without Mn, alloys containing Mn still exhibited better corrosion resistance. Among them, the FeCrMnAlCu high-entropy alloy demonstrated the best corrosion resistance, with a more positive corrosion potential (Ecorr = -0.417 V) and a smaller corrosion current density (Icorr = 2.120×10-6 A?cm-2). Furthermore, the FeCrMnxAlCu high-entropy alloys activated and formed discontinuous and loose corrosion product films.

    • Feng Li, Wang Zhaoqin, Zhao Yanchun, Zhang Wei

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230572

      Abstract:This study employs vacuum arc melting technology to fabricate FexCrMnAlCu (x=0, 0.5, 1, 1.5, 2) high-entropy alloys. The phase structure and microstructure of the alloys before and after corrosion were characterized using XRD, SEM, and EDS. The corrosion behavior and oxide film composition of the alloys in a 3.5% NaCl solution were investigated through potentiodynamic polarization curves, EIS, XPS, and immersion tests. The results indicate that FexCrMnAlCu high-entropy alloys exhibit a dual-phase structure of BCC+FCC. The addition of Fe enhances the intensity of the BCC phase diffraction peaks. As the Fe content increases, the alloy"s corrosion resistance initially improves and then deteriorates. Alloys with added Fe exhibit superior corrosion resistance compared to those without Fe. This is attributed to the change in grain size caused by the addition of Fe, which alters the number of grain boundaries per unit area, consequently affecting the corrosion resistance. The primary type of corrosion observed in FexCrMnAlCu alloys is intergranular corrosion. After corrosion, an oxide film composed of various elemental oxides forms on the alloy surface. The Fe1.5CrMnAlCu alloy exhibits the lowest self-corrosion current density (1.75×10-6 A/cm2), the most positive self-corrosion potential (-0.589 V), and the largest impedance arc radius.

    • zhaomeng, zhouhui, heyanchun, guibinhua, wangkeliang

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230575

      Abstract:TiN coatings are widely used in metal bipolar plate modification due to good corrosion resistance and electrical conductivity.The TiN deposition process is susceptible to formation non-metallic vacancies due to the preparation conditions, affecting the coating properties. Therefore, in this paper, the electronic structures of TiNx systems containing different amounts of nonmetallic vacancies are calculated using the first principle method, and a study of the effect of nonmetallic vacancies on the crystal structure, energy band structure, density of states, relative concentration of free electrons, and charge spreading of each TiNx system is carried out. The analytical results show that with the formation of nonmetallic vacancies, the stability of each TiNx system gradually decreases and the nonmetallic vacancy formation energy gradually increases. The relative concentration of free electrons of each TiNx system is calculated to be in the following order: TiN0.25>TiN>TiN0.5>TiN0.75.The electrical conductivity of the TiNx system is mainly affected by the combination of three factors: the metallization of the 3d orbital state of the Ti atoms, the reduction of the contribution of the N atoms to the 2p orbitals, and the decrease in the volume of the crystal cell due to the deletion of the N atoms.

    • Yu Yang, Geng Chen, Hui Li, Jinglong Liang, Meilong Hu, Mengjun Hu

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230580

      Abstract:High-entropy carbides (HECs) are materials with great potential as catalysts for the hydrogen evolution reaction (HER), but the production of nanoscale HECs remains a significant challenge. This study successfully prepared nanoscale (VNbTaZrHf)C HEC powders with a face-centered cubic (FCC) structure by electro-deoxidation of metal oxides and graphite in CaCl2 at 1173 K. The appropriate temperature conditions were favorable for suppressing the in-situ sintering growth of HEC particles. Electrochemical performance testing was carried out in 1M KOH to explore the catalytic performance of the (VNbTaZrHf)C HEC. The catalytic HER performance of (VNbTaZrHf)C HEC was evaluated through polarization curves, Tafel slope, electrochemical impedance spectroscopy, and double-layer capacitance value CV testing. The double layer capacitance value of (VZrHfNbTa)C is 40.6 mF/cm2. The larger double-layer capacitance value indicated a larger electrochemically active surface area. Due to the high-entropy effect and nanoscale structure of (VNbTaZrHf)C HEC, it exhibits superior catalytic HER performance and develops a novel method for the preparation of HECs via molten salt electro-deoxidation.

    • Zhang Wenbin, Yang Haijuan, Liu Cuirong, Li Yan, Shi Aizun

      Available online:November 22, 2023  DOI: 10.12442/j.issn.1002-185X.20230600

      Abstract:To save the cost of using nickel materials and fully utilize their excellent corrosion resistance, pure nickel N6 with a thickness of 1mm was selected as the flyer plate and medium carbon steel 45# with a thickness of 3mm was used as the base plate for explosive welding tests. The dynamic parameters were calculated through the explosive welding window, and the interface bonding morphology and elements were analyzed using metallographic microscopy (OM) and scanning electron microscopy (SEM). The mechanical properties of the composite plate were tested through shear tests, and the explosive welding process was simulated using AUTODYN. The results indicate that there is a "boundary effect" near the explosion point, and the bonding interface along the explosion welding direction changes from a straight shape to a stable wavy interface. The thickness of the element diffusion layer near the interface is 20um, and the wavy diffusion layer increases the bonding area, which is conducive to metallurgical bonding. The shear strength of the composite plate reaches 325.5Mpa. Analyzing the numerical simulation results, it was found that the interface morphology was consistent with the experimental results. The simulation results showed that the velocity and plastic deformation degree of the characteristic points were also consistent with the experimental results.

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    Latest number
    Rare Metal Materials and Engineering
    2023,Volume 52, Issue 11
    Editor in chiefPingxiang Zhang
    Associate editorYingjiang Shi
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