2025,Volume 54, Issue 3

>2025 Invited Manuscripts for Young Editorial Board

• Nanoflower Copper Sulfide as Cathode Materials for Magnesium Ion Batteries

  He Yuantai, Wu Liang, Shi Yongan, Zhong Zhiyong, Yao Wenhui, Pan Fusheng

  2025,54(3):545-553 DOI: 10.12442/j.issn.1002-185X.20240361

  Abstract(5) HTML(27) PDF(2.70 M)( 16)

  Abstract:CuS-C50, the cathode materials for magnesium ion batteries, was synthesized by adding the surfactant cetyltrimethyl ammonium bromide (CTAB) and adjusting the percentage of ethylene glycol to 50vol% in hydrothermal synthesis process. Results show that CuS-C50 has the complete nanoflower structure. In aluminum chloride-pentamethylcydopentodiene/tetrahydrofuran (APC/THF) electrolyte, the CuS-C50 exhibits a high specific capacity of 331.19 mAh/g when the current density is 50 mA/g and still keeps a specific capacity of 136.92 mAh/g over 50 cycles when the current density is 200 mA/g. Results of morphology characterizations indicate that the complete nanoflower structure can provide more active sites and reduce the barriers for Mg²⁺ movement, eventually improving the charge and discharge performance of the CuS cathode materials for magnesium ion batteries.

• Microstructure and Properties of Fe-Mo Functionally Graded Materials Fabricated by Electron Beam-Directional Energy Deposition

  lidanni, Yaozhengjun, Yaomengxin, Zhangshuxian, Oleksandr Moliar, Tetiana Soloviova, Iryna Trosnikova, Petro Loboda, Zhangshasha

  2025,54(3):554-568 DOI: 10.12442/j.issn.1002-185X.20240549

  Abstract(4) HTML(10) PDF(9.60 M)( 12)

  Abstract:Fe-Mo functionally graded materials (FGMs) with different composition-change rates from 100% 304 stainless steel to 100% Mo along the composition gradient direction were prepared by electron beam-directed energy deposition (EB-DED) technique, including three samples with composition mutation of 100%, composition change rate of 10% and 30%. Results show that the composition-change rate significantly affects the microstructure and mechanical properties of the samples. In the sample with abrupt change of composition, the sharp shift in composition between 304 stainless steel and Mo leads to a great difference in the microstructure and hardness near the interface between the two materials. With the increase in the number of gradient layers, the composition changes continuously along the direction of deposition height, and the microstructure morphology shows a smooth transition from 304 stainless steel to Mo, which is gradually transformed from columnar crystal to dendritic crystal. Elements Fe, Mo, and other major elements transform linearly along the gradient direction, with sufficient interlayer diffusion between the deposited layers, leading to good metallurgical bonding. The smaller the change in composition gradient, the greater the microhardness value along the deposition direction. When the composition gradient is 10%, the gradient layer exhibits higher hardness (940 HV) and excellent resistance to surface abrasion, and the overall compressive properties of the samples are better, with the compressive fracture stress in the top region reaching 750.05±14 MPa.

• Effect of Grain Size on Nano-scratching Behavior of Poly-crystalline γ-TiAl Alloy via Molecular Dynamics Simulation

  Cao Hui, Xu Hanzong, Li Haipeng, Li Haiyan, Chen Tao, Feng Ruicheng

  2025,54(3):569-580 DOI: 10.12442/j.issn.1002-185X.20240420

  Abstract(6) HTML(8) PDF(4.38 M)( 7)

  Abstract:The scratching mechanism of polycrystalline γ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method, with a focus on the influence of different grain sizes. The analysis encompassed tribological characteristics, scratch morphology, subsurface defect distribution, temperature variations, and stress states during the scratching process. The findings indicate that the scratch force, number of recovered atoms, and pile-up height exhibit abrupt changes when the critical size is 9.41 nm due to the influence of the inverse Hall-Petch effect. Variations in the number of grain boundaries and randomness of grain orientation result in different accumulation patterns on the scratch surface. Notably, single crystal materials and those with 3.73 nm in grain size display more regular surface morphology. Furthermore, smaller grain size leads to an increase in average coefficient of friction, removed atoms number, and wear rate. While it also causes a larger range of temperature values and distributions. Due to the barrier effect of grain boundaries, smaller grains exhibit reduced microscopic defects. Additionally, average von Mises stress and hydrostatic compressive stress at the indenter tip decrease as grain size decreases owing to grain boundary obstruction. This work is helpful to better understand the deformation mechanism of polycrystalline γ-TiAl alloy during the nano-scratching process.

• Design and Dynamic Experiment of Al-Cu Graded Materials Impactor with Strain Rate of 10⁴–10⁵/s

  Hu Jianian, Zhou Zizheng, Li Yidi, Chen Xiang, Yang Gang, Liu Jintao, Zhang Jian

  2025,54(3):581-586 DOI: 10.12442/j.issn.1002-185X.20240293

  Abstract(2) HTML(5) PDF(1.23 M)( 8)

  Abstract:Based on simplified calculations of one-dimensional wave systems, loading pressure platform curves of Al-Cu gradient materials (GMs) impactor were designed. The Al-Cu GMs were prepared using tape-pressing sintering, and their acoustic properties were characterized to match the design path. The parallelism of the Al-Cu GM was confirmed using a three-dimensional surface profilometry machine. A one-stage light-gas gun was used to launch the Al-Cu GM, impacting an Al-LiF target at a velocity of 400 m/s. The results of the experimental strain rate demonstrate that the Al-Cu GMs can realize the precise control of the strain rate within the range of 10⁴?10⁵/s in the high-speed impact experiments.

• Hot Isostatic Pressing for Enhancing Mechanical Properties of Mo Alloys Prepared by Laser Powder Bed Fusion

  Liang Xunwen, Fu Zhongxue, Zhang Shiming, Che Yusi, Cheng Pengming, Wang Pei

  2025,54(3):587-592 DOI: 10.12442/j.issn.1002-185X.20240583

  Abstract(3) HTML(8) PDF(2.09 M)( 13)

  Abstract:To enhance the mechanical properties of Mo alloys prepared through laser powder bed fusion (LPBF), a hot isostatic pressing (HIP) treatment was used. Results show that following HIP treatment, the porosity decreases from 0.27% to 0.22%, enabling the elements Mo and Ti to diffuse fully and to distribute more uniformly, and to forming a substantial number of low-angle grain boundaries. The tensile strength soars from 286±32 MPa to 598±22 MPa, while the elongation increases from 0.08%±0.02% to 0.18%±0.02%, without notable alterations in grain morphology during the tensile deformation. HIP treatment eliminates the molten pool boundaries, which are the primary source for premature failure in LPBFed Mo alloys. Consequently, HIP treatment emerges as a novel and effective approach for strengthening the mechanical properties of LPBFed Mo alloys, offering a fresh perspective on producing high-performance Mo-based alloys.

• Advances in Residual Stress Relief Strategies at Ceramic/Metal Joint Interfaces

  Wang Xingxing, Chen Benle, Jiang Yuanlong, Pan Kunming, Ren Xuanru, Yuan Zhipeng, Zhang Yulei

  2025,54(3):618-627 DOI: 10.12442/j.issn.1002-185X.20240477

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  Abstract:As service conditions become more challenging and production complexity increases, there is an increasing demand for enhanced comprehensive performance of ceramic/metal heterostructures. At present, brazing technique has been widely utilized for ceramic-metal heterogeneous joints. However, the residual stress relief in these welding joints is complicated and necessary. Because metals and ceramics have different properties, especially their coefficients of thermal expansion. Welding joints exhibit large residual stresses during the cooling process. The relatively high residual stresses may significantly degrade the joint properties. For this issue, four alleviation routes were reviewed: optimization of process parameters, setting an intermediate layer, surface structure modulation and particle-reinforced composite solder. The states and distribution patterns of residual stress in ceramic-metal brazed joints were summarized, and the generation and detection of residual stress were introduced. Eventually, upcoming prospects and challenges of residual stress research on ceramic/metal heterostructures were pointed out.

• Review on Enhancing Separation of Heavy Metal Ions by Cyclodextrin Adsorbent Materials

  Zhang Ning, Liu Jie, Zhang Xin, Zhao Yuxiu, Xue Zhixiao, Xia Wenxiang

  2025,54(3):628-639 DOI: 10.12442/j.issn.1002-185X.20240307

  Abstract(2) HTML(4) PDF(1.71 M)( 12)

  Abstract:The traditional techniques for treating wastewater contaminated by heavy metals mostly involve chemical precipitation, solvent extraction and adsorption, ion-exchange, chemical precipitation, and membrane separation. The main shortcomings of traditional procedures are low economic efficiency, lack of environmental friendliness, and poor selectivity. Cyclodextrins are artificial compounds that resemble cages. Through host-guest interaction, pollutants can be adsorbed by its stable inner hydrophobic chamber and exterior hydrophilic surface. It is not only inexpensive and environmentally friendly, but also quite selective. The synthesis and application of materials were reviewed, as well as the primary influencing factors, and the reaction principle of cyclodextrin adsorbent materials for better separation of heavy metal ions. And the future trend of discovery was described.

• Progress on Microstructure and Performance Optimization in H/MEAs Regulated by Single and Hierarchical Heterostructures

  Wang Bing, Li Chunyan, Wang Xinhua, Li Xiaocheng, Kou Shengzhong

  2025,54(3):640-664 DOI: 10.12442/j.issn.1002-185X.20240564

  Abstract(5) HTML(9) PDF(11.66 M)( 12)

  Abstract:The development of high-performance structural and functional materials is vital in many industrial fields. High- and medium-entropy alloys (H/MEAs) with superior comprehensive properties owing to their specific microstructures are promising candidates for structural materials. More importantly, multitudinous efforts have been made to regulate the microstructures and the properties of H/MEAs to further expand their industrial applications. The various heterostructures have enormous potential for the development of H/MEAs with outstanding performance. Herein, multiple heterogeneous structures with single and hierarchical heterogeneities were discussed in detail. Moreover, preparation methods for compositional inhomogeneity, bimodal structures, dual-phase structures, lamella/layered structures, harmonic structures (core-shell), multiscale precipitates and heterostructures coupled with specific microstructures in H/MEAs were also systematically reviewed. The deformation mechanisms induced by the different heterostructures were thoroughly discussed to explore the relationship between the heterostructures and the optimized properties of H/MEAs. The contributions of the heterostructures and advanced microstructures to the H/MEAs were comprehensively elucidated to further improve the properties of the alloys. Finally, this review discussed the future challenges of high-performance H/MEAs for industrial applications and provides feasible methods for optimizing heterostructures to enhance the comprehensive properties of H/MEAs.

• Effect of Solution Cooling Rate on Microstructure and Mechanical Properties of Ultra-high Strength Titanium Alloy TB17

  Ji Xiaoyu, Xu Jianwei, Zhang Yu, Li Mingbing, Zeng Weidong, Zhu Zhishou

  2025,54(3):665-670 DOI: 10.12442/j.issn.1002-185X.20240531

  Abstract(5) HTML(12) PDF(5.89 M)( 12)

  Abstract:The effects of different cooling rates on the microstructure evolution and tensile properties of TB17 titanium alloy were studied. The results show that the cooling rate has a significant effect on the microstructure. When the cooling rate is low, the alloying elements are diffused fully, resulting in higher content and larger size of coarse lamellar layers, and a small amount of secondary α phase is precipitated in the matrix. When the cooling rate is high, a large amount of microstructure at high temperature is preserved, so that the coarse lamellar content is low and the size is small, and the secondary α phase is hardly observed. Due to the absence of external forces, the lamellar α phase maintains a strict Burgers orientation correspondence with the β phase. The tensile property is greatly affected by the solution cooling rate. A large amount of secondary α phase is precipitated during air-cooling (AC), which results in the highest strength. Due to the faster cooling speed, only the coarse layer is retained during water-quenching (WQ), resulting in the lowest strength. The cooling rate of furnace-cooled (FC) is too slow, so the coarse lamellar growth is obvious. This inhibits the precipitation of secondary α phase, and leads to the middle intensity. After aging treatment, the tensile properties change differently. WQ has the highest strength, while FC has the lowest strength.

• Phase Field Simulation of Pressure-Assisted Sintering Process of Uranium Nitride

  Sun Qiming, Shen Wenlong, Liao Yuxuan, Li Yu, Wang Jijun, Liu Wenbo

  2025,54(3):671-678 DOI: 10.12442/j.issn.1002-185X.20240497

  Abstract(2) HTML(6) PDF(2.18 M)( 8)

  Abstract:The pressure applied during the sintering process plays an important role in improving the final density of UN pellets. In this work, a phase field model of UN pressure-assisted sintering was established by introducing elastic strain energy and particle rigid motion process. The effects of stress on the growth of sintering neck and rigid-body motion on the pore shrinkage were analyzed, and the multi-particle sintering process under the three mechanisms was simulated. The simulation results show that the length of the sintering neck and its growth rate increase with the increase in the applied strain. There is obvious stress concentration at both ends of the sintering neck, and the stress distribution gradually becomes uniform with the increase in time. With the increase in translational mobility, the pore shrinkage rate increases, and the densification completion time is advanced, while the value of rotational mobility has little effect on the pore shrinkage process. The model can capture the formation and growth of the sintering neck, the spheroidization and closure of the pores. The coordination grain number of large volume pores is higher and the existence time is longer.

• Microstructure and Mechanical Properties of TiAl Alloy Fabricated by Laser Melting Deposition

  Chen Yongning, Xiao Huaqiang, Chu Mengya, Mo Taiqian

  2025,54(3):679-687 DOI: 10.12442/j.issn.1002-185X.20240587

  Abstract(4) HTML(7) PDF(12.17 M)( 10)

  Abstract:Complex shaped TiAl alloy components can be manufactured by laser additive manufacturing technology, further expanding the engineering applications of this lightweight high-temperature alloy in the aerospace field. However, there is currently limited research on the intrinsic relationship among the laser melting deposition process, microstructure, and properties of TiAl alloys. TiAl alloy specimens with good macroscopic quality were prepared by laser melting deposition using Ti-48Al-2Cr-2Nb alloy powder as raw materials. The microstructure, phase composition, hardness distribution of the deposited layer, and room temperature mechanical properties of the deposited specimens were studied under optimized process parameters. The results show that the microstructure of the deposited layer mainly consists of a large number of γ-TiAl phases and a small amount of α₂-Ti₃Al phases; the microstructure of the deposited sample exhibits a layer characteristics formed by columnar crystals, equiaxial crystals, cytosolic crystals, and laths structure, and the grain refinement in the microstructure of the deposited layer is obvious. The hardness distribution of the deposited layer ranges from 537 HV_0.3 to 598 HV_0.3, and the Vickers hardness at the bottom is higher than that at the middle and the top. The ultimate compressive strength of the TiAl alloy specimens is (1545±64) MPa at room temperature, with a compressive strain of (17.68±0.07)%, and the ultimate tensile strength along the scanning direction of the laser is (514±92) MPa at room temperature, with an elongation of (0.2±0.04)% after break; the ultimate tensile strength along the building direction is (424±114) MPa, with an elongation of (0.15±0.07)% after break. The tensile fracture morphology of TiAl alloy specimens exhibits quasi cleavage fracture characteristics. By optimizing the scanning strategy and assisting with subsequent heat treatment, it is expected to improve the uniformity of alloy structure and the anisotropy of mechanical properties.

• Deep Penetration Mechanism of Dual Pulse TIG Welding for Medium-Thick Titanium Alloys

  Yang Qingfu, Luo Zhiwei, Zeng Caiyou, Jiang Zihao, Cong Baoqiang, Qi Bojin

  2025,54(3):688-696 DOI: 10.12442/j.issn.1002-185X.20240680

  Abstract(4) HTML(7) PDF(10.05 M)( 9)

  Abstract:In response to the issues of shallow TIG arc penetration and low welding efficiency in medium-thickness titanium alloy arc welding, TIG welding experiments were conducted on 6 mm-thick TC4 titanium alloy. The effects of different arc modes (direct current, low-frequency pulse, and low-frequency plus high-frequency dual-pulse) on the weld pool and weld bead formation were studied. Finite element simulation was employed to investigate the temperature field and flow field dynamics of the weld pool in dual-pulse welding, and the deep penetration mechanism of dual-pulse TIG welding was analyzed. The results show that compared to constant current and low-frequency pulse modes, the dual-pulse current mode increases the flow velocity of the weld pool, effectively excites the deep penetration keyhole at the center of the pool, promotes the downward movement of the heat source, and thus increases the penetration depth. The tensile strength of the dual-pulse TIG weld joint reaches 964 MPa, the joint strength coefficient is 98%, and the post-fracture elongation is 3.7%, achieving a near-equal strength match for the joint.

• Effects of Pulsed Magnetic Field Treatment on Tribological Properties of Cemented Carbide/Titanium Alloy

  Chen Zhe, Xu Yangyang, Yan Qiaosong, Chen Yitong, Zhang Lin, Wu Mingxia, Liu Jian

  2025,54(3):697-705 DOI: 10.12442/j.issn.1002-185X.20240525

  Abstract(2) HTML(6) PDF(13.28 M)( 10)

  Abstract:WC-Co cemented carbide balls with different cobalt (Co) contents were modified by pulsed magnetic field. The effects of pulsed magnetic field treatment on tribological properties of YG6/YG8/YG12-titanium alloy (TC4) were investigated by reciprocating friction machine and SEM. The results show that pulsed magnetic field treatment can effectively reduce the coefficient of friction (COF) of YG cemented carbides-TC4 titanium alloy friction pair. Main wear forms are adhesive wear and oxidation wear. Different intensities of pulsed magnetic field change the energy amount generated. Taking YG8 as an example, the average COF are reduced by 20.5%, 29.7%, and 25.9%, after the magnetic 0.5, 1, and 1.5 T treatments, respectively, compared with that without treatment. At magnetic field intensity of 1 T, the average COF of YG6, YG8, YG12 cemented carbide decreases by 19.5%, 29.7%, 20.1%, respectively. With the increase in Co content, the effect of the magnetic field treatment increases first and then decreases, and the magnetic field response is the most significant when the Co content is 8wt%. As an external energy, the pulsed magnetic field used on cemented carbide causes the Co phase from α-Co to ε-Co and thus results in dislocation proliferation; as a result, the ability of cemented carbide to resist plastic deformation is improved, and the corresponding macro-phenomenon is an increase in strength and wear resistance, so that the friction performance is finally improved.

• Microstructure and Mechanical Properties of Mg-4Y-3Nd-0.5Zr Alloy Fabricated by Wire Arc Additive Manufacturing

  Chang Zijin, Zhang Ruize, Zeng Caiyou, Yu Kai, Li Ziqi, Cong Baoqiang

  2025,54(3):706-713 DOI: 10.12442/j.issn.1002-185X.20240675

  Abstract(5) HTML(6) PDF(10.53 M)( 8)

  Abstract:A WE43 (Mg-4Y-3Nd-0.5Zr, wt%) magnesium-rare earth alloy thin-wall component was fabricated by wire arc additive manufacturing, and its microstructure and mechanical properties were investigated by multiscale characterization, microhardness, and tensile tests. The influences of direct aging (T5) and solid solution+aging (T6) on the microstructure evolution and mechanical properties were studied. Results indicate that the as-deposited WE43 alloy has a uniform equiaxed crystal matrix, with an average grain size of 25.3 μm. Reticulated eutectic structure (α-Mg+Mg₄₁Nd₅/Mg₂₄Y₅) is formed due to Nd and Y element liquid segregation at grain boundaries. Tensile strength of as-deposited alloys is 190 MPa. Peak hardness increases from 74 HV_0.2 to 91 HV_0.2 after T5 aging with persistence of significant eutectic structures. Peak aging hardness is 108 HV_0.2 after T6 treatment, and the eutectic structure is dissolved completely, while a small amount of Mg₂₄Y₅ remains in matrix. Tensile strength of alloys is enhanced to 283 MPa after T6 treatment, but it also induces significant grain growth and reduces the elongation in vertical direction more obviously than in horizontal direction.

• Johnson-Cook Constitutive Model and Failure Parameters of Mg-9Gd-4Y-2Zn-0.5Zr Alloy

  Zhi Huidong, Guo Baoquan, Ding Ning, Yan Zhaoming, Zhu Jiaxuan, Wan Chen

  2025,54(3):714-721 DOI: 10.12442/j.issn.1002-185X.20240505

  Abstract(5) HTML(8) PDF(3.83 M)( 8)

  Abstract:The mechanical behavior and fracture failure characteristics of Mg-9Gd-4Y-2Zn-0.5Zr alloy at various strain rates were investigated, including parameter calibration and verification based on the Johnson-Cook (J-C) constitutive model and failure model. Quasi-static tensile tests at different temperatures were conducted by a universal testing machine, while dynamic tensile tests at high strain rates (1000–3000 s^-1) were performed by a Hopkinson bar apparatus. Based on the experimental data, modifications were made to the strain rate hardening and thermal softening terms of the J-C constitutive model were modificated, and relevant model parameters were calibrated. Further numerical simulations were carried out; the fracture locations and true stress-strain curves between experimental and simulated results were compared to validate the reliability of the failure model parameters. The fracture morphology of the magnesium alloy was observed and the microstructural characteristics influencing failure under different temperatures and strain rates were explored. Both dimples and cleavage steps were observed in the fracture morphologies during quasi-static and dynamic tensile processes, indicating a mixed fracture mechanism. Slightly more cleavage steps are found at higher strain rates, which is related to the strain rate sensitivity of the magnesium alloy. In contrast, ductile fracture is predominant during high-temperature tensile tests.

• Research Progress on Effects of Rare Metals on Marine Atmospheric Corrosion Behavior of Steel

  Liu Feiyang, Li Tianke, Wang Ruixin, Guo Bin, Ai Yuanlin, Tang Yu

  2025,54(3):791-802 DOI: 10.12442/j.issn.1002-185X.20240533

  Abstract(11) HTML(2) PDF(5.77 M)( 5)

  Abstract:Steel material is the main structural material of marine equipment, but its corrosion usually occurs in the marine atmosphere environment, thus affecting its service performance. Compared with general atmospheric corrosion, marine atmospheric corrosion is affected by sea salt aerosols, chloride ions and other specific factors of marine atmosphere. In addition, the marine atmospheric corrosion properties of steel materials are closely related to the alloying elements of the materials. This paper reviewed the relevant studies of worldwide scholars on the effect of rare metal doping on the marine atmospheric corrosion resistance of steel materials in recent years, and summarized the corrosion mechanism of carbon steel, stainless steel, weathering steel and other common structural steels under marine atmospheric environment. The effects of Nb, Mo, Sb, Sn, Ce, La, Y and other rare metal elements on the marine atmospheric corrosion resistance of steel materials were analyzed. For weathering steel and carbon steel, the effect of rare metal elements on the structure of rust layer was mainly discussed. For stainless steel, the effect mechanism of rare metal elements on inclusion modification and pitting behavior of stainless steel was discussed. The future research directions were prospected, in order to provide references for the application of rare metal doped steel in marine atmospheric environment and for the improvement of marine atmospheric corrosion resistance.

• Research Progress on High-Temperature Oxidation Protection of TiAl Alloys

  Ye Xinyu, Wu Liankui, Cao Fahe

  2025,54(3):803-817 DOI: 10.12442/j.issn.1002-185X.20240508

  Abstract(4) HTML(9) PDF(5.45 M)( 8)

  Abstract:The TiAl alloy is considered a promising material for aerospace and other high temperature applications due to its low density, high strength and excellent creep resistance. However, its application is currently limited by its poor oxidation resistance above 750 ℃. In this paper, the classification, development, and high temperature oxidation behavior of TiAl alloys were reviewed. The formation mechanism and structural evolution of oxide films were discussed. The research progress of the preparation processing, bulk alloying, reinforcing phase and surface modification technologies aimed at improving the high temperature oxidation resistance of TiAl alloys since the 21st century were summarized. Furthermore, the application of theoretical calculation in oxidation process was discussed and the development trend of this field was prospected.

• Research Progress on Brazing Copper with Dissimilar Materials

  Long Fei, Song Kexing, Zhang Zhaoqi, Wang Ce, He Peng, Sun Jun

  2025,54(3):818-836 DOI: 10.12442/j.issn.1002-185X.20240629

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  Abstract:The basic properties, structural, and functional applications of copper were described and the process characteristics and joint properties of copper brazing were and analyzed. The current research status of brazing between copper and dissimilar materials such as steel, aluminum, titanium, ceramics, and carbon-based materials were reviewed and examples of studies on brazing copper with heterogeneous structures were listed. Specific considerations in the brazing process were also examined, including brazing filler metal selection, process formulation, interlayer design, use of brazing equipment, and performance inspection. The importance of joining structure and joint interface design was emphasized. Furthermore, it is proposed that the development direction of copper brazing should focus on being green, intelligent, reliable, and low-cost, providing a technical reference for the engineering applications of copper and the brazing fabrication of heterogeneous structures containing copper.

>Materials Science

• Solid-Solution Heat Treatments Effect on Microstructure and Mechanical Properties of Low-Oxygen TZM Alloy

  Xing Hairui, Shi Qianshuan, Hu Boliang, Li Shilei, Li Yanchao, Wang Hua, Wang Qiang, Xu Liujie, Feng Rui, Zhang Wen, Hu Ping, Wang Kuaishe

  2025,54(3):593-603 DOI: 10.12442/j.issn.1002-185X.20240560

  Abstract(1) HTML(5) PDF(4.08 M)( 5)

  Abstract:Low-oxygen TZM alloy (oxygen content of 0.03vol%) was subjected to solid-solution heat treatment at various temperatures followed by quenching. Results show that the tensile strength of the alloy gradually decreases with the increase in solid-solution temperature, and the elongation first increases and then decreases. The the amount of nanoscale Ti-rich phases precipitated in low-oxygen TZM alloys gradually increases with the increase in solid-solution temperature. Special strip-shaped Ti-rich areas appear in the samples solidified at 1200 and 1300 °C. The nanoscale Ti-rich phases ensure the uniform distribution of dislocations throughout TZM alloy, while significantly improving the plasticity of low-oxygen TZM alloy samples.

• Trial Production of Heavy-Duty Metal Rubber Based on Predictive Model of Relative Density Mechanics

  Hao Huirong, Wang Jiawei, Zhao Wenchao, Ren Jiangpeng

  2025,54(3):604-611 DOI: 10.12442/j.issn.1002-185X.20240116

  Abstract(1) HTML(5) PDF(2.00 M)( 10)

  Abstract:The predictive model and design of heavy-duty metal rubber shock absorber for the powertrains of heavy-load mining vehicles were investigated. The microstructural characteristics of the wire mesh were elucidated using fractal graphs. A numerical model based on virtual fabrication technique was established to propose a design scheme for the wire mesh component. Four sets of wire mesh shock absorbers with various relative densities were prepared and a predictive model based on these relative densities was established through mechanical testing. To further enhance the predictive accuracy, a variable transposition fitting method was proposed to refine the model. Residual analysis was employed to quantitatively validate the results against those obtained from an experimental control group. The results show that the improved model exhibits higher predictive accuracy than the original model, with the determination coefficient (R²) of 0.9624. This study provides theoretical support for designing wire mesh shock absorbers with reduced testing requirements and enhanced design efficiency.

• Quantitative Strengthening Evaluation of Mg-Zn-Y Alloys Containing Icosahedral Quasi-Crystalline Phase

  Wang Yingnan, Meng Xiaokai, Guo Junhong

  2025,54(3):612-617 DOI: 10.12442/j.issn.1002-185X.20240183

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  Abstract:Mg-4.8Zn-0.8Y, Mg-18Zn-3Y, Mg-15Zn-5Y, Mg-30Zn-5Y and Mg-42Zn-7Y (wt%) alloys containing icosahedral quasi-crystalline phases were prepared using the ordinary solidification method. The impact of Mg matrix porosity on the tensile strength and hardness of the alloys was studied. The porosity of the Mg matrix was quantitatively assessed using scanning electron microscope and Image-Pro Plus 6.0 software. Tensile tests were conducted at room temperature. Results show that the maximum tensile strength of the alloy is 175.56 MPa, with a corresponding Mg matrix porosity of 76.74%. Through fitting analysis, it is determined that the maximum tensile strength is achieved when the porosity of the Mg matrix is 64.87%. The microhardness test results indicate a gradual decrease in alloy hardness with increasing the porosity of Mg matrix. This study provides an effective quantitative analysis method for enhancing the mechanical properties of magnesium alloys.

• Microstructure and Properties of Al-Zn-Mg-Cu-Zr Alloy with Low Scandium Content

  Zhu Biwu, Xiao Gang, Liu Xiao, Ye Fan, Zhang Wei, Cui Xiaoli, Zhan Haihong, Liu Wenhui

  2025,54(3):722-729 DOI: 10.12442/j.issn.1002-185X.20240552

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  Abstract:The relationship between the mechanical properties and precipitation behavior of Al-Zn-Mg-Cu-Zr aluminum alloys with low Sc content (0.02wt%, 0.07wt%, 0.12wt%) was investigated by OM, SEM, TEM, and universal material testing machine. With the increase in Sc content, microstructure of as-cast alloy is gradually refined, and the coarse secondary phase at the grain boundary increases, thus weakening the effect of fine grain strengthening. In the alloy at rolling+T6 state, the Al₃(Sc,Zr) phase inhibits the precipitation of the main strengthening phase η', and the inhibition effect becomes more obvious with the increase in Sc content, thus weakening the precipitation strengthening effect. The grain refinement is conducive to the formation of more and finer dimples during the tensile deformation, thus improving the ductility of the alloy. The low Sc content alloy (0.02wt%) shows the excellent mechanical properties after rolling and T6 heat treatment, whose tensile strength and elongation are 683 MPa and 21%, respectively.

• Preparation of Fe₃O₄@SiO₂@CM-β-CD Magnetic Nanomaterials and Its Their Adsorption Properties on Er(Ⅲ)

  Zhao Yuxiu, Liu Jie, Zhang Ning, Zhang Xin, Xue Zhixiao, Zhang Qiulu, Li Qianting

  2025,54(3):730-740 DOI: 10.12442/j.issn.1002-185X.20230715

  Abstract(3) HTML(5) PDF(4.70 M)( 6)

  Abstract:Fe₃O₄ magnetic nanoparticles were prepared by co-precipitation method, the surface of the magnetic particles was modified by SiO₂ and CM-β-CD, and Fe₃O₄-based magnetic nanomaterials (Fe₃O₄@SiO₂@CM-β-CD) with high adsorption properties were prepared. Single factor optimization experiments were carried out, and the physical and chemical properties of magnetic nanocomposites were characterized by TEM, EDS and BET. The adsorption behavior of Fe₃O₄@SiO₂@CM-β-CD on rare earth Er(Ⅲ) was investigated. The effects of adsorbent dosage, temperature and rotational speed on erbium removal rate were also investigated. The results show that when the dosage of SDBS is 1 g, the dosage of TEOS is 6 mL, the dosage of APTES is 1 mL, and the dosage of CM-β-CD is 0.5 g, the adsorption rate of Er(Ⅲ) can preferably reach more than 95%. When the contact time is 30 min, the initial concentration of Er(Ⅲ) is 10 mg/L, the initial pH is 4.5, the dosage of adsorbent is 30 mg, the temperature is 298 K, and the rotational speed is 150 r/min, the removal rate of Er(Ⅲ) is about 98%. After the adsorption of erbium, the nanomaterials were desorbed with 0.1 mol/L HNO₃ for 20 min, and the desorption efficiency of rare earth Er(Ⅲ) can be more than 87%. The adsorption mechanism of Fe₃O₄@SiO₂@CM-β-CD was investigated by XPS analysis. It is found that the adsorption of Fe₃O₄@SiO₂@CM-β-CD on Er(Ⅲ) is mainly by the inclusion of cyclodextrin cavity, supplemented by electrostatic adsorption and chemisorption. The results of this study can provide a new method for efficient recovery of rare earth elements with low concentration in aqueous solution.

• Microstructure and Oxidation Resistance of Self-Passivating W-Si-Zr Alloys

  Zhang Shirong, Chen Shijie, Wang Rui, Ye Chao, Xue Lihong, Zhou Qilai, Yan Youwei

  2025,54(3):741-746 DOI: 10.12442/j.issn.1002-185X.20230722

  Abstract(4) HTML(5) PDF(4.70 M)( 4)

  Abstract:Self-passivating W-Si-Zr alloys were prepared by mechanical alloying and spark plasma sintering. Microstructures of alloys were characterized by XRD, XPS, SEM and EPMA, and their oxidation resistance was tested. The results show that the alloy contains W-enriched, W₅Si₃, SiO_x (x=1, 1.5, 2) and ZrO_x (x=1, 1.5, 2) phases. The W₅Si₃ phase distributes continuously. SiO_x and ZrO_x particles are dispersed in the matrix with the sizes of 1.0–2.5 μm and 0.7–2.7 μm, respectively, and ZrO_x particles are often associated with SiO_x particles. The W₅Si₃ plays a key role in the oxidation resistance of the alloy. The addition of Zr contributes to the formation of W₅Si₃ phase, whose area reaches 70.2%. The oxidation rate of W-Si-Zr alloy is about 1/2 of that of W-Si alloy and 1/36 of that of pure W at 1000 ℃ in the air.

• Effect of Mg on Cast Microstructure and Mechanical Properties of S44660 Super Ferritic Stainless Steel

  Fan Wenjie, Ning Likui, Chang Dongxu, Ding Dong, Li Guanglong, Liu Enze, Tan Zheng, Tong Jian, Li Haiying, Zheng Zhi

  2025,54(3):747-754 DOI: 10.12442/j.issn.1002-185X.20230724

  Abstract(3) HTML(5) PDF(7.03 M)( 5)

  Abstract:To study the effect of Mg on super ferritic stainless steel, the content of Mg in S44660 super ferritic stainless steel was adjusted, and four kinds of test steels without Mg and with Mg additions of 0.0002%, 0.0004% and 0.0010% (mass fraction) were prepared. The effects of Mg on the cast microstructure and mechanical properties of S44660 super ferritic stainless steel were studied. The results show that the average grain size of the steel decreases from 1.14 mm to about 0.83 mm after 0.0002% Mg is added, and with the further increase in Mg content to 0.0004% and 0.0010%, the average grain size decreases to about 0.62 and 0.59 mm. It is confirmed that Mg can refine the grain of S44660 steel. Typical inclusion type of the S44660 steel is Ti-O-N composite inclusion, while it changes into Ti-O-Al-Mg-N composite inclusion after adding Mg, and the inclusion content and size decrease at the same time. The yield strength and tensile strength of the steel increase after adding Mg. Therefore, Mg can improve the impact absorption energy and hardness of S44660 super ferritic stainless steel.

• Effects of Rare Earth La-Yb Doping on Microstructure and Electrochemical Performance of Magnesium Alloys Used as Anode for Seawater Batteries

  Yang Qingzhu, Lian Lixian, Liu Ying

  2025,54(3):755-764 DOI: 10.12442/j.issn.1002-185X.20230730

  Abstract(6) HTML(4) PDF(8.33 M)( 6)

  Abstract:AZ91-La-Yb magnesium alloy as anode of seawater batteries was prepared by combining mechanical alloying with spark plasma sintering processes. The effects of rare earth La-Yb doping on the microstructure and electrochemical behavior of AZ91 anode were studied. The results show that the AZ91-La-Yb alloy prepared by mechanical alloying-spark plasma sintering processes consists of equiaxed grains. On the one hand, La-Yb doping results in the formation of micron-scale (0.5–2 μm) RE-rich phase that are uniformly distributed at grain boundaries. This phase is mainly composed of rare earth metals (RE=La, Yb) and Mg(RE) solid solution. On the other hand, the plastic deformation caused by discharge plasma sintering and the doping effect of rare earth elements La-Yb significantly improve the morphology of β-Mg₁₇Al₁₂ phase, transforming from a coarse network structure to a slender elongated shape. The combination of uniform distribution of nearly micron-scale RE-rich phase and the smaller β phase promotes the uniform dissolution of magnesium alloys and effectively alleviates localized corrosion of magnesium alloys. Compared to the AZ91 anode magnesium alloy, the AZ91-La-Yb alloy doped with rare earth La-Yb exhibits more stable discharge voltage and excellent discharge performance. At a current density of 20 mA/cm², its specific capacity can reach 1068 mAh/g, and the anode utilization efficiency is 50.4%.

• Microstructure， Thermal and Mechanical Properties of γ Phase in Mn-rich NiMnGa Alloy

  Zhou Yuecong, Ouyang Sheng, Deng Cuizhen, Long Jian

  2025,54(3):765-773 DOI: 10.12442/j.issn.1002-185X.20230736

  Abstract(3) HTML(3) PDF(6.38 M)( 4)

  Abstract:Brittleness of traditional Ni-Mn-Ga alloy is a marjor obstacle for its practical applications, as actuators and sensors. The Ni-rich Ni-Mn-Ga alloy can significantly improve the ductility. However, the shape memory strain is significantly reduced. Higher martensitic transformation temperature, good thermal stability and moderate shape memory property are shown in Mn-rich Ni-Mn-Ga. In the present work, microstructural feature, mechanical properties and thermal property of Ni₅₄Mn_28+xGa_18-x(x=0, 4, 7, 9, 13) were investigated. As the Mn content increases, the γ phase appears, with is a face centered tetragonal (fct) structure, and a γ grain contains a hierarchical "nano-lamellae forming within micro-lamellae" microstructure. A micro-lamella consists of two variants, each variant has a pair of nano-lamellae, and they are {011} twin related. Owing to the introduction of lamellar γ, the ductility is improved. With the increase in Mn content, the compressive stress increases from 914 MPa to 2175 MPa, and the compressive strain increases from 14% to 26%. The martensitic transformation temperature of such series of alloys increases from 352 ℃ to 585 ℃. For Mn-rich Ni-Mn-Ga alloy, the ductility improvement is inferior to that of Ni-rich alloy, but the martensitic transformation temperature is higher.

• Effects of Cr and Zr on Interface Microstructures and Properties of CuW/CuCr Integral Materials

  Yang Xiaohong, Liu Zixian, Li Xuejian, Xiao Peng, Liang Shuhua

  2025,54(3):774-780 DOI: 10.12442/j.issn.1002-185X.20230737

  Abstract(5) HTML(6) PDF(3.44 M)( 12)

  Abstract:CuW/CuCr integral materials with Cu-Cr-Zr powder interlayer was prepared by integral sintering infiltration method. The effects of Cr and Zr content and solution aging heat treatment on the microstructure and properties of the interface and both sides of the material were studied. The results show that with the increase in Zr content in Cu-15%Cr-x%Zr (mass fraction, similarly hereinafter) interlayer, the eutectic phase amount on CuCr side of the integral material increases, and the conductivity at CuCr end decreases. The hardness increases first and then decreases. At the same time, the addition of Zr promotes the diffusion of Cr into W. The tensile test bars of integral materials with different interlayers were prepared, and the interfacial tensile strength was tested and the fracture morphology was analyzed. It is found that when the Zr content in the interlayer is 0.5%, the interfacial tensile strength of the whole material reaches the maximum value of 517 MPa, which is 18% higher than that of the CuW/CuCr integral material with Cu-15%Cr interlayer without Zr. The tearing edge of Cu phase in the tensile fracture becomes shallower and shorter, and the number of cleavage fractures of W particles increases, which indicates that the interfacial strength of Cu/W phase and the end strength of CuCr are improved.

• Diffusion Behavior of Elements at Cu/Ti Bimetallic Liquid-Solid Composite Interface

  Shao Peng, Chen Xuan, Huang Sheng, Yu Kun, Chen Hao, Liu Kun, Xiao Han

  2025,54(3):781-790 DOI: 10.12442/j.issn.1002-185X.20230745

  Abstract(4) HTML(6) PDF(6.69 M)( 4)

  Abstract:The Cu-Ti bimetallic composites were prepared by liquid-solid composite process, and the diffusion behavior of Cu and Ti elements at the composite interface was investigated by OM, SEM, EPMA and other testing methods. The results show that the grain boundaries are the main channels for diffusion in the process of Cu/Ti composite. Except for part of the Cu₄Ti phase formed on the Cu matrix, the rest of the compound phases of the diffusively-dissolved layer are generated on the Ti matrix. The compounds generated at the Cu-Ti composite interface are Cu₄Ti, Cu₃Ti₂, CuTi and CuTi₂, where the Cu₃Ti₂ phase grows in a “jagged” manner, the CuTi phase grows in a “bamboo shoot” manner, and the CuTi₂ phase grows in a “planar” manner. The hardness values of the diffusion-dissolved layer are significantly higher than those of the two pure components. As verified by the Miedema model, the sequence of interfacial phase precipitation is CuTi, Cu₃Ti₂, CuTi₂ and Cu₄Ti. The bonding of Cu and Ti is a combined action of Cu diffusion in Ti matrix and Ti dissolution in the Cu solution.

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• Effects of Acetylene Gas on Mechanical Properties of DLC Film Prepared by Plasma-Enhanced Chemical Vapor Deposition

  Li Tong, Chang Yi Xiang, Zhang Tong, Zhang Yi, Yin Yan Sheng, Lu Jin Lin

  Available online:March 06, 2025  DOI: 10.12442/j.issn.1002-185X.20240677

  Abstract(25) PDF(1.10 M)(25)

  Abstract:Diamond-like carbon (DLC) films have many advantages,such as high hardness, low friction coefficient, and high chemical stability. They have been widely used for improving the surface hardness and wear resistance of light alloys. To improve the mechanical properties of 2024 aluminum alloy, a kind of DLC film was deposited on the surface of 2024 aluminum alloy by plasma-enhanced chemical vapor deposition technique.?The effects of acetylene gas on the microstructure, hardness, wear resistance and adhesion of DLC film were investigated by field emission scanning electron microscopy, nano-indentation, friction-wear test. The results indicate that the thickness of the?DLC film increased gradually with increasing the proportion of acetylene. There is an obvious transition layer between the DLC film and matrix. When the ratio of argon to acetylene is 1:3, the hardness of the DLC film was enhanced significantly because of the changes in the content of sp3 and sp2 bonds within the film. At the same time, the coefficient friction of the DLC film was reduced. This work provides an experimental and theoretical basis for improving the mechanical properties and enhancing durability of aluminum alloys.

• Research on the mechanism of pure copper binder jetting additive forming and sintering densification

  Lv Shaobo, Yang Yongqiang, Wang Di, Liu Linqing, Wu Shibiao, Zhang Shiqin, Jiang Fei

  Available online:March 06, 2025  DOI: 10.12442/j.issn.1002-185X.20240835

  Abstract(28) PDF(1.59 M)(17)

  Abstract:The printing process and the debinding sintering process are carried out step by step, which can realize the pure copper processing with high laser reflectivity and high thermal conductivity. The process parameters of pure copper binder jetting additive manufacturing were studied. The effects of powder layer thickness and inkjet density on green parts forming performance were studied. At the same time, the effects of sintering atmosphere and sintering temperature on the densification process of the parts were studied. The results show that the combination of powder layer thickness of 75μm and inkjet density of 50% can ensure the density and compression strength of green parts, and have high dimension precision and high surface quality. The driving force in hydrogen atmosphere is stronger than that in vacuum, and the surface oxide layer can be effectively reduced by the introduction of hydrogen. The density of 1060°C was 77.70% , the carbon residue formed pores to restrain the sintering process, and the density of 1070°C was 93.94% . It points out the direction for further optimizing the manufacturing process of binder jetting with pure copper.

• Research progress on the preparation of rhenium and rhenium alloy coatings under mild conditions

  wanghaoyan, Zhu Lian, wangzhen, baishuxin, yeyicong, tangyaguo

  Available online:February 26, 2025  DOI: 10.12442/j.issn.1002-185X.20240571

  Abstract(8) PDF(1.32 M)(17)

  Abstract:Rhenium has excellent physical and chemical properties, and has important applications in aerospace and military fields as ultra-high temperature structural material and surface cooling coating. There are many preparation methods for Re coating, but the mainstream preparation technology has high deposition temperature and corrosive atmosphere, which corrodes most refractory metal substrates. As a result, the mainstream preparation technology can not obtain dense and well-bonded Re coating on refractory metal and alloy substrate surface, which makes its application in high temperature protection of refractory metal surface limited. The preparation technology of Re coating under mild conditions is expected to solve this problem. This paper reviews the research status of Re coating preparation methods under three mild conditions: aqueous electrodeposition, MOCVD and EBPVD. The preparation processes and typical structure characteristics of Re coating by different methods are summarized, and the future research direction is prospected.

• Discrete element simulation and experimental study on the W-Cu homogeneous composites processed by high-pressure torsion

  Wang Xue, Zhu Yahui, Yang Cen, Gan Guoqiang, Li Ping, Xue Kemin

  Available online:February 26, 2025  DOI: 10.12442/j.issn.1002-185X.20240577

  Abstract(7) PDF(1007.33 K)(17)

  Abstract:The discrete element simulation of high-pressure torsion (HPT) deformation of W-Cu homogeneous powder material was carried out by PFC-3D software. The force chain and displacement distribution of particles during compression and torsion deformation were analyzed, and their effects on porosity, coordination number and equivalent stress in different regions were discussed. The simulation results indicate that the particle displacement exhibits a gradient distribution along both the compression direction and radial direction, with the maximum displacement located at the sample edge and on the upper surface. During the compression stage, particle rearrangement reduces the porosity rapidly, while shear deformation further promotes secondary particle rearrangement and rotation, which leads to a gradual decrease of porosity. The relative density and coordination number at the sample edge are higher than at the center, indicating that shear deformation with large torsional radius favors powder densification. Under the conditions of 400 °C and 1.5 GPa, HPT deformation was applied to the cold-pressed W-30Cu powder compacts with different turns. The experimental results show that with the increase of torsional radius and HPT turns, the degree of particle breakage, microstructure refinement and homogeneity are improved significantly. Under the combined effect of high hydrostatic pressure and shear force, the pores were elongated and enclosed, which results in the relative density increasing from 95.44 ± 0.87% after 10 turns to 96.03 ± 0.54% after 20 turns. The crystallite size of tungsten significantly reduces to 20.8 nm and the dislocation density rapidly increases to 2.35×101? m?2 after 15 turns and then the grain refinement and dislocation accumulation achieve the dynamic equilibrium. After 20 turns, due to the combined effects of powder densification, microstructure refinement and dislocation accumulation, the microhardness at the samples edge reaches 334.8 ± 4.2 HV, which represents an increase of approximately 78.7% compared to the sample center after 10 turns.

• Preparation and research progress of high temperature superconductors based on high pressure technology

  HuLe, HouHongli

  Available online:February 26, 2025  DOI: 10.12442/j.issn.1002-185X.20240592

  Abstract(3) PDF(825.78 K)(14)

  Abstract:From the discovery and preparation of metallic mercury superconductors to nickel-based superconductors, the study of the physical properties and microscopic mechanisms of superconducting materials has greatly promoted the development of condensed matter physics. The development of practical high-temperature superconductors based on new preparation technologies plays an extremely important role in the fields of strong and weak electricity. As a new means, high-pressure experimental technology has become one of the powerful tools for exploring novel superconductors and increasing the superconducting transition temperature (Tc) of superconductors. This paper takes three high-temperature superconductors H3S, LaH10 and HgBaCuO prepared by high pressure and high temperature as the objects, systematically summarizes the research progress of using high-pressure technology to control the superconductivity of high-temperature superconductors, explains the internal organization evolution of high-temperature superconductors under high pressure, clarifies the preparation ideas of practical high-temperature superconductors and the regulation mechanism of high pressure on their organization and superconductivity. The following main conclusions are drawn through analysis: high pressure helps to prepare LaH10, a hydrogen-rich compound superconductor with a special crystal structure, so that it can obtain a higher superconducting transition temperature; at the same time, high pressure can also affect copper oxide superconductors in a similar way to changing doping, thereby changing their superconductivity. High pressure technology is an effective way to obtain high temperature superconductors with special crystal structures (layered and cage). This paper reviews and analyzes the preparation technology of high temperature superconductors with high superconducting transition temperature and its progress, which can provide theoretical basis and experimental basis for the preparation of new high temperature superconductors by high pressure physics experiments.

• Interfacial and Mechanical Property Comparison of Cu/Al Composite Plates Manufactured by Rolling and Underwater Explosive Welding

  Available online:February 18, 2025  DOI: 10.12442/j.issn.1002-185X.20240745

  Abstract(34) PDF(1.11 M)(30)

  Abstract:Cu/Al composites are widely utilized across various industries due to their lightweight and excellent electrical conductivity. However, the impact of different manufacturing methods on the interfacial structure and mechanical properties of these composites remains significant. In this study, Cu/Al composite plates were fabricated using rolling and underwater explosive welding techniques to systematically compare their interfacial microstructure and mechanical performance. Interface morphology, grain orientation, grain boundary characteristics, and phase distribution were analyzed through optical microscopy, scanning electron microscopy, and electron backscatter diffraction. Mechanical properties were assessed using tensile shear tests, 90° bending tests, and hardness measurements, with Vickers hardness and nanoindentation tests providing further insight into hardness distributions. The results indicate that the diffusion layer in rolled Cu/Al composites is relatively fragile, while those produced by underwater explosive welding feature a diffusion layer approximately 18 μm thick, metallurgically bonded through atomic diffusion. The tensile shear strength of these composites ranges from 64.14 to 70.84 MPa, with superior flexural performance demonstrated in the 90° three-point bending test by the underwater explosive welded samples. This study elucidates the effects of distinct manufacturing methods on the interfacial properties and mechanical performance of Cu/Al composites, offering essential insights for selection of manufacturing method and application.

• Effect of Decreasing Homogenization Temperature on Microstructure and Properties of 2024-T3 Alloy

  Wang Yali, Cao Lingfei, Wen Qinghong, Jiang Yuan, Wu Xiaodong

  Available online:February 17, 2025  DOI: 10.12442/j.issn.1002-185X.20240689

  Abstract(13) PDF(1.35 M)(21)

  Abstract:The effect of decreasing the homogenization temperature on the microstructure and mechanical properties of 2024-T3 alloy was investigated. The results show that the area fractions of the residual coarse secondary phases after homogenization at 430 ℃ or 460 ℃ for 24 h followed by rolling are close to each other, and both are higher than that of the alloy homogenized at 490 ℃ for 24 h as routinely used in the industry. The alloys with homogenization of 430 ℃/24 h or 460 ℃/24 h and solution treatment have higher recrystallization fractions and finer grain sizes due to the PSN (Particle Stimulated Nucleation) effect of the coarse secondary phase. Hardness tests and tensile tests show that the peak hardness, tensile strength, yield strength, and elongation of the three alloys are relatively close to each other. Therefore, appropriately decreasing the homogenization temperature can improve the uniformity of grain size, reduce the cost, and maintain the excellent tensile properties of 2024-T3 plates. Whereas the high-temperature homogenization of 490 ℃/24 h can make the 2024-T3 sheet have relatively good plasticity and toughness.

• Quantitative Analysis of Low Cycle Fatigue Fracture Stress in Nickel-Based Single Crystal Superalloys based on crack tip plastic zone

  Liu Xinling, Deng Zhiwei, Tian Fuzheng, Wang Xueyun, Li zhen

  Available online:February 17, 2025  DOI: 10.12442/j.issn.1002-185X.20240731

  Abstract(7) PDF(1.11 M)(31)

  Abstract:Low cycle fatigue failure is the main failure mode of tenon part of single crystal turbine blades. Due to the difference between the actual working load and the design load, the stress leading to fatigue failure often needs to be given after fatigue failure, and the fracture is a comprehensive reflection of load and temperature. Quantitative analysis of the fracture and inverse fatigue stress have important engineering application value in blade failure analysis. The unique microstructure and crystal structure of single superalloy make its fatigue fracture characteristics different from those of polycrystalline materials. The main fatigue fracture characteristics of single crystal superalloy are slip plane rather than fatigue band. A model and method for quantitative analysis of crack tip plastic zone are presented in this paper. There is a certain Angle between fatigue fracture and load of single superalloy, which is a composite cracking mode rather than a type Ⅰcracking mode. According to the cracking characteristics of single superalloy,, in this paper, using the test data of DD6 single-crystal high-temperature alloy under the condition of 530 ℃ and strain ratio r=0.05, the hysteresis return line of its different life intervals is analyzed, and the results show that: the life span is between one thousand and ten thousand times, and its hysteresis loop is very narrow; the life span is greater than ten thousand times, and its hysteresis loop is basically a straight line; it shows that DD6 single-crystal high-temperature alloy under the conditions of 530 ℃ and strain ratio r=0.05 has the small yielding characteristics. Based on this, for the low-week fatigue fracture, the characteristics of crack initiation and extension stage and its fracture characteristics were studied, and a quantitative analysis model of fatigue stress fracture was established by considering the composite cracking and based on rp in the plastic zone at the crack tip, use a total of 12 crack locations a for 3 specimens, the quantitative analysis of fatigue stress fractures at different a locations is carried out, and the analysis results show that the error of fatigue initiation stress was within 1.3 times, and that of inverse extrapolation result of the first stage of extension was within 1.5 times of the dispersion band. The results provide models and methods for quantitative fracture analysis of stresses in single-crystal high-temperature alloys mainly by slip-surface cracking (non-fatigue strips).

• Effects of the addition of CNTs on microstructure, mechanics and thermal conductivity of pure copper in laser powder bed melting

  Laixia Yang, Longbo Zhang, Qidong Xie, Yanze Zhang, Mengjia Yang, Feng Mao, Zhen Chen

  Available online:February 17, 2025  DOI: 10.12442/j.issn.1002-185X.20240754

  Abstract(22) PDF(1019.58 K)(46)

  Abstract:The laser powder bed fusion (L-PBF) process for manufacturing copper typically exhibits poor strength-ductility coordination； the addition of enhancers is usually an effective way to improve it. However, there is relatively limited research on Cu composites. To explore the impact of enhancements on Cu, we used a Cu-CNTs mixed powder as the base and applied the L-PBF technology to produce a Cu-CNTs composite. We studied its forming performance, microstructure, and mechanical properties, as well as its conductive and thermal properties. The resulting composite has a high relative density of consolidated Cu-CNTs material. The addition of CNTs results in non-uniform microstructure with equiaxed grains at the edges of the melt pool and columnar grains at the center. Compared to pure copper, the overall mechanical properties of the composite are improved (tensile strength increased by 52.8%, elongation increased by 115.9%), and the electrical and thermal properties are also enhanced (thermal conductivity increased by 10.8%, electrical conductivity increased by 12.7%). The results indicate that the addition of CNTs can increase the tensile strength and elongation, as well as the electrical and thermal properties of copper. Therefore, this material provides an efficient pathway for designing more efficient heat sink structures.

• Effect of pore structure on forming quality and performance of Mg-5Zn magnesium alloy porous bone repair scaffold fabricated by SLM

  Zhao Lun, Sun Zhichao, Wang Chang, Zhang Pengsheng, Tang Shuai, Zhang Baoxin

  Available online:December 02, 2024  DOI: 10.12442/j.issn.1002-185X.20240618

  Abstract(125) PDF(1.94 M)(112)

  Abstract:Four types of Mg-5Zn porous scaffolds with different pore geometries, including body-centered cubic (BCC), rhombic dodecahedron (RD), primitive (P), and gyroid (G), were designed and fabricated using SLM. Their forming quality, compression mechanical properties, and degradation behavior were investigated. The results indicate the scaffolds fabricated exhibited good dimensional accuracy, and the surface chemical polishing significantly improved the surface quality while reducing forming errors. Compared to the rod structures (BCC, RD), the surface structures (G, P) scaffolds had less powder particle adhesion. For the same design porosity, the G porous scaffold exhibited the best forming quality. The predominant failure mode of scaffolds during compression was a 45° shear fracture. At a porosity of 75%, the compression performance of all scaffolds met the compressive performance requirements of cancellous bone, and BCC and G structures showed relatively better compression performance. Immersed in Hank"s solution for 168 hours, the B-2-75% pore structure scaffold exhibited severe localized corrosion, with fractures in partial pillar connections. In contrast, the G-3-75% pore structure scaffold mainly underwent uniform corrosion, maintaining structural integrity, and the corrosion rate and loss of compressive properties are less than those of the B-2-75% structure. After comparison, the G-pore structure scaffold is preferred.

• Research on Welding Characteristics of Titanium Alloy Joints by Hollow cathode vacuum arc Welding

  Xu Jianping, Gong Chunzhi

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240470

  Abstract(40) PDF(1.20 M)(107)

  Abstract:The microstructure of Ti-6Al-4V joints by hollow cathode vacuum arc welding with different gas flow rate was studied, and the tensile properties were investigated. The results show that the microstructure of base metal was mixture of α phase β phase. The microstructure of heat affected zone are equiaxed and primary α and needle martensite α′ dispersed in the transformed β. Two kinds of tissues distribution depends on the heat-affected area affected by the welding thermal cycle.The microstructure of welding seam consists mainly of α′ martensite phase. Reduce welding gas flow rate and increase welding energy density, resulting in coarsening and more scattered distribution of martensitic grains. The tensile strength of welded joint is higher than that of base metal.

• Construction of bimodal-grained Mg-Bi alloy composed of ultrafine grains and fine grains and its strengthening and toughening mechanisms

  mengshuaiju, songjinlong, chenkeyi, cuimin, wanglidong, biguangli, caochi, yangguirong

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240480

  Abstract(69) PDF(921.12 K)(148)

  Abstract:Low-temperature equal channel angular pressing (ECAP) processing technology has great potential in fabricating bimodal-grained alloys composed of ultrafine grains and fine grains. Besides, fine grain Mg-Bi based alloys demonstrate excellent low temperature plastic deformation performance. Based on this, a new inverse temperature field ECAP (ITF-ECAP) processing method was developed to realize the severe plastic processing of a fine grained Mg-6Bi (B6) alloy at low temperature (<100 ℃) to construct a bimodal-grained microstructure composed of ultrafine (<1 μm) and fine grains (1-10 μm). The microstructure and mechanical properties characterization results show that dynamic recrystallization preferentially occurred at the initial grain boundaries of the fine-grained B6 alloy during the multi pass ITF-ECAP processing. Besides a large amount of submicron sized Mg3Bi2 phase precipitated during ITF-ECAP processing. As a result, bimodal-grained microstructure consisting of ultrafine grains with an average grain size (AGS) of about 600 nm and fine grain region with an AGS of about 2 μm was successfully constructed in B6 alloy through 4-pass ITF-ECAP processing. The volume fraction of the ultrafine grain region accounts for about 72.5 %. Due to the combined effects of grain-boundary strengthening, precipitation strengthening, dislocation strengthening, and back stress strengthening, the bimodal-grained B6 alloy exhibits excellent strength and ductility, with yield strength and elongation reaching 315.6±3.6 MPa and 22.3±1.0 %, respectively.

• Research Progress in Preparation of Titanium Matrix Composite Coatings by Cold Spraying: A Review

  Xu Yaxin, Zou Han, Huang Chunjie, Li Wenya

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240483

  Abstract(89) PDF(1.45 M)(166)

  Abstract:Cold spraying has great advantages in preparation of oxidization-sensitive metallic coatings because of the lower heat input and almost no oxidation resulting from its low temperature process. Combined with the convenience of cold spraying in manufacturing particle reinforced composite coatings, titanium matrix composite coatings prepared by cold spraying can compensate for the shortcomings of poor wear resistance of pure titanium or titanium alloys. In addition, one can also get the functional coatings besides the structural coatings. According to the existing research reports, the deposition behaviors and mechanisms of cold-sprayed titanium matrix composite coatings were summarized. By analyzing the porosity and deposition efficiency, the effect of strengthening on the microstructure of the cold-sprayed titanium matrix composite coatings was explained. The mechanism of reinforcement on mechanical and wear performance of titanium matrix composite coatings were revealed. Finally, the future application of cold-sprayed titanium matrix composite coatings is prospected, and several promising directions are listed.

• Analysis of the SLM forming structure and cracking mechanism of ZGH451 nickel-based high-temperature alloy

  wuyin, Zhang Hao, Zhu Yuping, Fang Shimin, Ding Yaoyao, Liang Liwen, Yan Guangqiang, Qiu Zixiang, Wang Haixuan, Dongye Shengshua, Tian Miaocheng, Yang Yang, Huang Qizhong, Zheng Yongjian

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240487

  Abstract(61) PDF(1.65 M)(135)

  Abstract:This study focuses on the SLM (Selective Laser Melting) formed ZGH451 nickel-based superalloy, revealing the mechanism by which solidification liquid films lead to crack initiation and clarifying the roles of alloy elements and texture in forming crack defects. Experimental results indicate that cracks in the SLM process of ZGH451 nickel-based superalloy can be mainly categorized into internal solidification cracks and edge cold cracks. During the late solidification stage, low-melting-point phase liquid films exist between dendrites, and high-melting-point Cr element particles at the solidification front hinder melt feeding. The insufficient feeding and thermal stress between dendrites cause the liquid film"s rupture, leading to solidification cracks in the core of the material. In the alloy"s contour region, high cooling rates and significant thermal stress lead to residual stress accumulation, which exceeds the material"s strength limit or grain boundary cohesion strength, resulting in the formation of cold cracks. When the input laser energy density is below 53.6 J/mm3, pores and lack of fusion defects increase significantly in the alloy, while exceeding 130.9 J/mm3 sharply increases the probability of keyhole formation along the melt pool track. These defects can induce cracks under stress. The more TiC and other carbide particles precipitate between dendrites, the greater grain misorientation, and the higher the alloy"s crack sensitivity. The deposited state of ZGH451 nickel-based superalloy is mainly composed of γ and γ" phases, with a preferred orientation on the (100) plane. The average aspect ratio of the grains reaches 11.25, and the significant texture exacerbates stress concentration at the grain edges and tips, promoting crack initiation and altering crack propagation direction.

• The Effect of Different Heat Treatments on Surface Microstructures and Anodic Oxide Film Structures of an Al-5.6Mg Alloy Sheets

  jiangzhongyu

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240492

  Abstract(26) PDF(833.41 K)(150)

  Abstract:The effect of different intermediate annealing heat treatments on the surface microstructures and anodic oxide film structures of rolled sheets of an Al-5.6Mg alloy was studied. The results show that when the continuous annealing is used instead of the static state annealing in intermediate annealing process to control microstructures of the sheets, the surface grain size of the sheets can be reduced by about 60 %, and size of the Mg precipitated phase (Mg2Al3) can be reduced by about 67 %. Under the combined influence of grain size, uniform precipitation phase, and texture, the highest glossiness can be obtained, which was attributed to continuous intermediate annealing and stabilization annealing at low temperature. The uniform grain and precipitation structures is beneficial to reduce the inhomogeneous dissolution of the oxide film and to obtain the anodic oxide film with uniform thickness and high gloss.

• The Influence of Ni Interlayer Thickness on the Microstructure and Mechanical Properties of Zr-4/Nb/Ni/316SS Diffusion Bonded Joint

  Li Qianru, Zhang Fan, Niu Shiyu, Wang ying, Yang Zhenwen

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240495

  Abstract(60) PDF(1.24 M)(180)

  Abstract:This study systematically investigates the influence of Ni interlayer thickness on the microstructure, mechanical properties, and corrosion resistance of Zr-4/Nb/Ni/316SS diffusion bonded joints. The experimental results reveal that the typical interface microstructure of the joints consists of Zr-4/β-(Zr, Nb)/Nb/Ni3Nb/Ni/316SS. The shear strength of the joints initially increases and subsequently decreases with increasing Ni interlayer thickness, reaching a peak value of 380 MPa at an interlayer thickness of 30 μm. To elucidate the effect of Ni interlayer thickness on the mechanical properties, the microstructural characteristics of the joint interfaces were characterized, and Abaqus simulations were conducted to analyze the residual stress distribution across the interfaces. The comparative analysis of the mechanical properties and fracture behavior, combined with simulation results, indicates that while thicker Ni interlayers are more effective in alleviating residual stress, excessively thick interlayers lead to a reduction in shear strength due to their enhanced ductility. Additionally, the corrosion resistance of the joints was assessed using full immersion corrosion tests. The results indicate that the corrosion rate decreases with a reduction in Ni interlayer thickness, with the optimum corrosion resistance observed at an interlayer thickness of 10 μm. In conclusion, it is recommended that the Ni interlayer thickness be maintained between 10 μm and 30 μm to achieve a balance between mechanical properties and corrosion resistance.

• Study on thermal stability of W-Re alloy and influence of high temperature oxidation behavior temperature

  Nan Lingxin, Qi Yanfei, Xu Pengfei, Li Yungang, Pang Binghe

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240509

  Abstract(126) PDF(1.33 M)(160)

  Abstract:Superalloy has a very important position in the development of nuclear fusion and other fields, and the use of the requirement is to form a stable and protective oxide under high temperature service conditions, and the oxide can prevent further oxidation of the alloy. In order to study the stability and oxidation resistance of W-3%Re alloy at high temperature, the thermal stability experiments of W and W-3%Re alloy were carried out at (500,700,900 ℃) for 6h. Oxidation experiments were carried out at different temperatures (700,800,900 ℃) for 18h. The phase composition, oxidation kinetics, oxidation products and surface morphology of the oxide film were analyzed by XRD, SEM, LSM800 automatic 3D morphology analyzer and Hysitron TI Premier Nanoindentation apparatus. The results show that the quality of the alloy increases with the extension of oxidation time. During the oxidation process, the grain size of W-3%Re alloy is reduced, the oxidation film can be formed faster, the surface oxide layer is gradually thicker, and the high temperature oxidation resistance of W-3%Re alloy is improved. Compared with W, the chemical stability of the Re oxide in W-3%Re alloy is higher, and it shows a lower oxidation rate constant when it is oxidized at 700℃ for 18h. At this time, the W-3%Re alloy is a weak oxidation grade, and the density of the oxide layer is improved to a certain extent during the oxidation process. The results show that the addition of Re can improve the high temperature oxidation resistance of W material.

• Influence of silicide precipitation on mechanical properties in Ti-Al-Zr-Sn-Mo -W-Si system titanium alloy

  Zhang Xiaoyuan, Li Fuguo, Du Yuxuan, Liu Xianghong, Wang Kaixuan, Li Jieyao, Song Minglong

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240444

  Abstract(36) PDF(1.26 M)(113)

  Abstract:Comparative analysis of the differences in tensile strength and impact toughness between the TC25 alloy and TC25G alloy of Ti-Al-Zr-Sn-Mo-W-Si system titanium alloys was carried out, and the root causes of the differences in impact toughness between the two alloys and the alloy strengthening mechanism were elucidated through the observation of the SEM fracture morphology and the analysis of the TEM microscopic deformation mechanism. The results show that the precipitated phase in the impact fracture of TC25G alloy is ZrSi or TiZrSi compounds, which plays the role of second-phase reinforcement and is conducive to the enhancement of the alloy strength, and the precipitates are conducive to the extension of impact cracks, thus reducing the impact toughness of the alloy. TC25 alloy impact fracture microstructure cracks generally extend along the primary α phase phase boundary, while TC25G alloy impact fracture microstructure cracks through the primary α phase; so that the TC25 alloy crack extension path longer, and thus the alloy has a higher impact toughness. TEM observations show that the number of dislocation slip traces and dislocation plugging in TC25G alloy is significantly higher than that in TC25 alloy. The presence of a large number of plugged dislocations in the vicinity of the precipitates in TC25G alloy results in significant strengthening, leading to a higher strength of the alloy.

• Effects of temperature and twin boundaries on the mechanical properties and Protevin-Le chatelier(PLC) effect

  Gao Yubi, Wang Wenjuan, Yang Hui, Wang Xingmao, Xu Jiayu, Zhen Bing, Ding Yutian

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240445

  Abstract(18) PDF(2.83 M)(165)

  Abstract:In this paper, EBSD, SEM, TEM and quasi-static uniaxial tensile tests were used to study the effects of temperature and twin boundaries on the mechanical properties and Protevin-Le chatelier（PLC) effect of GH3625 alloy. The results show that with the increase of annealing temperature (1000 °C~1160 °C), the recrystallized grains of the annealed specimen grow, resulting in the annihilation of part of the annealed twin boundaries, which reduces the content and strength of the annealed twin boundaries of the alloy. And it is found that the lower the annealing temperature, the greater the critical strain value of the alloy with PLC. At the same time, the tensile deformation of the annealed specimen at 25 °C and 290 °C is mainly dominated by dislocation slip and deformation twin, while at 565 °C, the dislocation slip is mainly dominated by dislocation slip, and a large number of lamination faults are formed. With the increase of deformation temperature, dislocations tend to pass through grain boundaries and annealed twin boundaries, resulting in PLC, weakened grain boundary strengthening effect, and decreased alloy strength. In addition, the specimen with an annealing temperature of 1000 °C has an excellent combination of strength and plasticity in the temperature range of 25 °C~565 °C, which is mainly attributed to the interaction of pre-existing fine grains and a large number of annealed twin boundaries with dislocations, as well as the combined effect of deformed twins and lamination faults formed during tensile deformation. In addition, it is found that the twin content and deformation temperature have a significant effect on the rheological amplitude of the PLC.

• Research progress on the effect of hydrogen on the structure and properties of amorphous alloys

  Lichunyan, Liu Jianhui, Li Chunling, Fu Xiaoqiang, Li Xiaocheng, Kou Shengzhong

  Available online:November 21, 2024  DOI: 10.12442/j.issn.1002-185X.20240276

  Abstract(35) PDF(2.49 M)(14)

  Abstract:Compared with traditional crystalline materials, amorphous alloys have good hydrogen permeability and hydrogen storage capacity, and have great application prospects in the field of new energy. Therefore, it is of great significance to study the effect of hydrogen on amorphous alloys. In this paper, the effects of hydrogen on the structure, thermal stability and amorphous forming ability of amorphous alloys are reviewed, and the mechanism of the effects of hydrogen on the properties of amorphous alloys is described. This paper provides a theoretical basis for the study of the application of amorphous alloys in the field of new energy such as hydrogen storage, and has important practical significance to promote the functional application of amorphous alloys, so as to help realize the goal of "double carbon" in China..

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