10 June 2025, Volume 35 Issue 3

    

• Select all
  |

Experts Forum
• Select
  Research progress on preparation and strengthening methods of W-Cu alloys for electrical contacts

  YIN Cailiu, YANG Ming, YI Chunqiang, ZHANG Xinjiang, XU Zhengbin, WANG Xiufei

  Powder Metallurgy Industry. 2025, 35(3): 1-11. https://doi.org/10.13228/j.boyuan.issn1006-6543.20250090

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  In high-voltage power transmission systems, W-Cu electrical contact alloys are subjected to complex environments involving high-temperature arc ablation, SF6 gas erosion, and mechanical wear, necessitating a combination of high conductivity, strength-toughness, and corrosion resistance. This paper systematically reviews the microstructure regulation mechanisms of preparation technologies such as electroless plating, melt infiltration, spark plasma sintering (SPS), mechanical alloying, and microwave sintering, and discusses the influence of different processes on the interfacial bonding characteristics of W/Cu. The study comprehensively analyzes The effects of metal particles, ceramic phases, and fiber reinforcements in enhancing arc erosion resistance through mechanisms such as grain refinement strengthening and second-phase strengthening, while summarizing the synergistic regulation mechanisms of reinforcement phase morphology distribution and interfacial reactions on the material's overall performance. Current research demonstrates that multicomponent composite reinforcement systems effectively mitigate the conductivity-mechanical property trade-off. For instance, microwave-sintered materials with nano dual-phase reinforcement maintain high electrical conductivity even under significant hardness improvement. Future efforts should focus on developing core-shell structured nano-reinforcements, external field-assisted sintering technologies, machine learning design platforms, and full-lifecycle performance evaluation systems to address the challenge of conductivity-strength synergy. With the integration of multidisciplinary approaches, W-Cu alloys are expected to deliver next-generation high-performance contact material solutions for smart grids and extreme-environment electrical devices.
Research and Development
• Select
  Effect of TiB₂ on microstructure and mechanical properties of Al-Zn-Mg-Cu aluminum alloy

  ZHANG Kang, SHI Zimu, WANG Xingfu, LIANG Juhua, HAN Fusheng

  Powder Metallurgy Industry. 2025, 35(3): 12-21. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240014

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The effects of 1% TiB₂ particles as reinforcing phase on the microstructure and properties of Al-Zn-Mg-Cu alloy were studied. Al-6Zn-3Mg-Cu aluminum alloy and TiB₂/Al-6Zn-3Mg-Cu composite material were prepared using Spark Plasma Sintering (SPS) technology. The desired samples were obtained after hot forging, hot extrusion, and T6 heat treatment, followed by the study and analysis of the samples' microstructure and mechanical properties. The results indicate that there is no macroscopic segregation of alloy elements, and TiB₂ particles are uniformly distributed in the aluminum alloy matrix. The grain size of the aluminum-based composite material modified with TiB₂ is refined, the defects and pore aggregation in the structure are reduced, and the TiB₂ promotes the uniform distribution of MgZn₂ precipitation phase in the matrix. Due to the combined effects of grain refinement, improvement of microstructure, age-hardening precipitation of MgZn₂, and reinforcement from TiB₂ particles, the TiB₂/Al-6Zn-3Mg-Cu composite material achieves ultimate tensile strength, yield strength, and elongation of 539 MPa, 495 MPa, and 10.3%, respectively, showing improvements over the Al-6Zn-3Mg-Cu alloy in all three aspects.
• Select
  Microstructure and properties of powder metallurgical Ti80 alloy treated by ultrasonic surface rolling process

  YAO Jing, LI Xingyi, LIU Xiao, LIU Zhongqiang, LÜ Yuanzhi, XIAO Zhiyu

  Powder Metallurgy Industry. 2025, 35(3): 22-29. https://doi.org/10.13228/j.boyuan.issn1006-6543.20230166

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The surface of sintered Ti80 alloy was strengthened by surface ultrasonic rolling (USRP) technology, and the microstructure and properties of Ti80 alloy before and after rolling were analyzed by optical microscope (OM) and scanning electron microscope (SEM). The results show that the surface strengthening effect of the sample is the best when the rolling amplitude is 10 μm. The densification effect of the sample after rolling is remarkable. The surface hardness is increased by 18.5% and the surface roughness is reduced by 86%. The tensile strength and yield strength of rolled Ti80 alloy are 992 MPa and 815 MPa, respectively, which are 15.2% and 1.3% higher than those of sintered samples, and the elongation is increased from 1.7% to 2.6%. After soaking in 4 mol/L hydrochloric acid solution for eight days, the weight loss rates of sintered and rolled titanium alloys were 20.6 mg/cm² and 10.6 mg/cm², respectively, and the weight loss rate was reduced by 48.5%, which effectively improved the corrosion resistance of Ti80 alloy.
• Select
  Preparation of Inconel738 powder for laser cladding by plasma rotating electrode process

  ZHANG Xintao, ZHANG Kecui, ZHANG Dong, LU Sujun, FENG Zhen, ZHOU Hua

  Powder Metallurgy Industry. 2025, 35(3): 30-35. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240011

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Inconel738 powder for laser cladding was prepared using plasma rotating electrode method. Three factor and four level orthogonal experiments were conducted on the powder preparation process, and powder detection, morphology, and microstructure observation were carried out on the obtained process.The results show that the Inconel738 powder prepared by plasma rotating electrode method at a speed of 22 000 r/min, a current intensity of 650 A, and a feed rate of 1.3 mm/s could achieve a powder yield of 91.0%, The powder has a flowability of 10.7 s/50 g and a loose density of 4.78 g/cm³ the oxygen content of 0.68×10^-4,the sphericity of 92%. The powder has good sphericity, smooth surface, almost no hollow powder, and a dendritic structure inside and outside, which can be used for laser cladding.
• Select
  Characterized on M50NiL powder fabricated by plasma rotating electrode atomization method

  LI Shunjie, LI Jiwen, ZHANG Xin, WANG Zhenshuai, LIU Wei, XU Liujie

  Powder Metallurgy Industry. 2025, 35(3): 36-42. https://doi.org/10.13228/j.boyuan.issn1006-6543.20230118

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Using metallographic microscope, scanning electron microscope, oxygen-nitrogen analyzer, laser particle size analyzer, and X-ray diffraction analyzer, the characteristics of M50NiL powder prepared by plasma rotating electrode process （PREP), including the microstructure and phase composite, nitrogen-oxygen content, particle size distribution, and flowability were characterized. The results indicate that the powder has a relatively narrow particle size range, primarily distributed between 30-53 μm, with a unimodal distribution and a Gaussian distribution curve. The average particle size is 45.21 μm. The chemical composition of the powder is uniform, with high purity and no other impurities. Metal powder has low nitrogen-oxygen content with the below 0.024% of the oxygen and the below 0.025% of the nitrogen. The M50NiL powder with different particle sizes are primarily composed of α phase. The solidification structure varies with the change of the particle size: 15-53 μm consists of fine cellular and dendritic structures, whereas 53-150 μm is dendritic, and >150 μm is characterized by coarse equiaxed crystal structures. M50NiL powder has excellent physical properties and meets the technical requirements of powder bed fusion additive manufacturing.
• Select
  Injection molding of Al₂O₃ ceramics with microcrystalline wax based binder

  LI Gemin, YUAN Jiankun, CHEN Ruizhi, CHEN Pengqi, CHENG Jigui

  Powder Metallurgy Industry. 2025, 35(3): 43-48. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240037

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Using injection molding technology to produce near-net shaped Al₂O₃ ceramics can overcome the cutting difficulties caused by the high hardness of the ceramics. However, the commonly used paraffin based binders for injection molding have some deficiencies such as volatile paraffin components and easy phase separation during the injection process. Al₂O₃ powder with D₅₀ of 1.345 µm was injection molded using a new microcrystalline wax based binder. Effects of the injection parameters on the green density, the debinding ways and debinding temperature on the debinding rate, and the sintering temperature on the microstructure and property of the sintered Al₂O₃ ceramics were investigated. The results show that defect free injection green bodies can be obtained with injection temperature of 145 ℃, injection pressure of 7 MPa, holding pressure of 8 MPa, and mold temperature of 25 ℃. After debinding at 50 ℃ in trichloroethylene for 10 h and thermal debinding, the brown bodies are sintered at 1 550 ℃ for 4 h and the sintered samples with a relative density above 97%, a volume shrinkage rate of 45.5%, a microhardness over 15 GPa, a bending strength of 290 MPa can be obtained.
• Select
  Effect of element Y on the corrosion resistance of Cu-Ni-Sn-xY alloys

  LIU Xiaoxiong, DING Zipeng, LI Zhen, LU Songlin, ZHOU Tianqi, YANG Guirong

  Powder Metallurgy Industry. 2025, 35(3): 49-57. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240020

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Cu-12.5Ni-5Sn-xY alloys with different Y contents were prepared by spark plasma sintering (SPS), the effect of trace rare earth Y addition on the microstructure and corrosion behavior was investigated, and the corrosion mechanism of Cu-12.5Ni-5Sn-xY alloys were discussed. The results show that the addition of trace rare earth Y can overall improve the uniformity of the microstructure and grain size, and improve the corrosion resistance of the alloy. When the content of rare earth Y varies in the range of 0 wt% to 1.0 wt%, the corrosion resistance of Cu-12.5Ni-5Sn alloys first increases and then decreases, the Cu-12.5Ni-5Sn-0.7Y alloy possesses lower self-corrosion current density (1.116×10^-5 A/cm²) and lower corrosion rate (0.266 mm/a), the corrosion depth decreases by 63.8% compared with Cu-12.5Ni-5Sn without Y addition, and the corrosion resistance is better. Rare earth Y improves the densification and stability of the film layer by promoting the uniform distribution of Ni elements. The internal corrosion layer consists mainly of NiO, the intermediate layer consists mainly of SnO, and the surface layer consists mainly of CuO, Cu₂O and Cu₂(OH)₃Cl. Meanwhile, Y₂O₃ is formed on the surface of the alloy, which effectively preventing the attack of corrosive ions and improving the corrosion resistance of Cu-12.5-Ni-5Sn alloy.
• Select
  The low-frequency electromagnetic properties of FeSiAl powder modified by atomic layer deposition of Al₂O₃

  ZHOU Rui, GUO Yang

  Powder Metallurgy Industry. 2025, 35(3): 58-63. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240067

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Flaky FeSiAl (FSA) powders exhibit poor impedance matching and microwave absorption properties due to their high dielectric constant. To address this issue, the Al₂O₃ nanocoatings were applied onto the surface of FSA powders using the atomic layer deposition technique. Subsequently, the physical phase composition and electromagnetic properties of the FSA-based composites using scanning electron microscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, and a vector network were analyzed. Significant changes in the electromagnetic parameters and low-frequency microwave absorption properties of the FSA-based composites with varying deposition periods were revealed. Specifically, when the deposition cycle is set to 66, the FSA-based composites exhibites optimal low-frequency microwave absorption properties. At a thickness of 3.5 mm, these composites demonstrate an effective absorption bandwidth of 0.39 GHz and a minimum reflection loss of -14.11 dB. This improvement can be primarily attributed to the reduction in the dielectric constant of the FSA powder achieved through the Al₂O₃ nanocoating, which optimizes impedance matching while preserving the strong electromagnetic wave attenuation capability of the FSA.
• Select
  Stability of powder-in-tube Bi2223 superconducting cable-in-conduit conductor in liquid helium temperature region

  HU Zewen, WANG Qingxiang, LIU Jian

  Powder Metallurgy Industry. 2025, 35(3): 64-69. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240055

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Using an improved powder method combined with a multi-pass bundle drawing technique, a Bi2223/Ag superconducting tape was prepared. Metallographic inspection showes that the deformation of Bi2223 powder core wires in the final superconducting tape is uniform, and the proportions of silver to superconducting area in the tape are stable and uniform. A multi-layer tape stacked superconducting cable conductor is designed and stability simulations of the superconducting cable conductor under complex electromagnetic conditions in magnetic confinement fusion magnets are conducted using THEA code. This involves calculating and analyzing the conductor's current sharing temperature （T_cs） at 4.2 K under different current and background magnetic fields. It also simulates the impact of energy shocks （200~300 mJ/cm³） during plasma disruption events （20~30 ms） on conductor stability. Simulation results demonstrates that the superconducting conductor designed has good stability. Under the impact of energy higher than that of plasma disruption, the local temperature rises quickly and reaches a peak in a very short time and then rapidly returns to the initial temperature. The maximum temperature is lower than T_cs.
• Select
  The adsorption mechanism of hydrogen and its content control in boron carbide-alumina pellet

  WANG Wei, ZHANG Xinnan, CHEN Xiangyang, SUN Yue, BAI Xue, LIU Yuyang, YANG Lei, WANG Pengyu, WANG Zhigang, LU Junqiang, WANG Xingming

  Powder Metallurgy Industry. 2025, 35(3): 70-76. https://doi.org/10.13228/j.boyuan.issn1006-6543.20250076

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  This study systematically examines the effects of sintering temperature and desorption treatment on hydrogen content in boron carbide-alumina (WABA) pellets through inert gas fusion-thermal conductivity method. The results demonstrate that elevating the sintering temperature from 1 300 ℃ to 1 590 ℃ reduces hydrogen content by 69.3%. Research on desorption post-treatment shows that the core block exhibits three-stage dehydrogenation characteristics, including pore adsorbed water (<120 ℃, hydrogen content 93.996×10^-6), deep hole condensation water and internal crystallization water (120-550 ℃, hydrogen content 22.211×10^-6), bound hydroxyl groups and residual organic matter (>550 ℃). When RH<30%, the hydrogen content can be reduced to 17.583×10^-6. Helium demonstrates superior dehydrogenation performance compared to argon, achieving 42.2% higher desorption efficiency and enabling hydrogen reduction below 10×10^-6 at RH <30%. Notably, secondary hydrogen absorption occurs when environmental humidity exceeds RH>70%. Process capability analysis confirms stable manufacturing control with CPK values consistently above 2.0 across multiple batches. These findings establish critical theoretical and technical guidelines for hydrogen management in WABA pellets production and quality assurance.
• Select
  Selective laser melting of 316LN stainless steel

  YANG Xinyue, YANG Yuying, ZHAO Dingguo, SUN Xin, HU Zhangyan, SUN Yingjie

  Powder Metallurgy Industry. 2025, 35(3): 77-86. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240150

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The process of preparing high nitrogen steel by selective laser melting of high nitrogen stainless steel powder under normal pressure exhibits nitrogen escape, which cannot effectively produce qualified high nitrogen stainless steel. This study prepared 316LN powder by using CrN as a nitrogen enhancer and formed 316LN high nitrogen steel samples using atmospheric pressure selective laser melting method. The influence of process parameters on the formation of high nitrogen stainless steel was investigated. The nitrogen content, nitrogen emissions, phase composition, microstructure, and microhardness of the obtained 316LN high nitrogen steel sample were analyzed using hydrogen oxygen analyzer, X-ray diffraction, and electron back scatter diffraction. The results show that as the laser density increases, the density of the sample showes a trend of first increasing and then decreasing, reaching a maximum value of 95.33% at 138.89 J/mm³. The nitrogen content of the powder decreases with increasing energy density, and the microstructure is mainly composed of small cellular and columnar crystals, with austenite as the main phase. The strength of 316LN powder formed samples shows a certain upward trend with the increase of energy density, while the elongation rate shows a downward trend. Within the range of laser energy density (69.44-182.29 J/mm³), the highest elongation of the 316LN powder formed sample is 21.56%. Overall, when the laser energy density is 130.21 J/mm³ (laser power of 250 W, scanning speed of 800 mm/s, scanning spacing of 0.08 mm, powder thickness of 0.03 mm), the 316LN powder selective laser melting formed sample exhibits excellent mechanical properties.
• Select
  Effect of B₄C content on properties of hot-pressed SiC/Al composites

  WANG Haitao, FAN Zimin, TANG Mingqiang, ZHAO Fang, LIN Chen, LE Chen, CHEN Yihua

  Powder Metallurgy Industry. 2025, 35(3): 87-91. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240021

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  SiCp/B₄Cp hybrid reinforced aluminum matrix composites were prepared by hot press sintering method. The density, mechanical properties, physical phase composition, microstructure, friction coefficient and its wear were investigated. The results show that with the increase of B₄C content, the density decreased gradually. When the B₄C content is 10%, the densification can reach 99.89%. When the B₄C content is 25%, the hardness reaches 79 HRB; the flexural strength increases and then decreases, and when the B₄C content is 10%, it reaches 559.47 MPa. The coefficient of friction of the specimen and the amount of abrasion of the specimen are the smallest when the B₄C content is 20%, which are 0.17 and 3.61×10^-6 g/m, respectively.
• Select
  Effect of trace amount of CeO₂ addition on the microstructure and mechanical properties of W-Ni₃Al-Co alloy

  LIU Jingming, HU Lulu

  Powder Metallurgy Industry. 2025, 35(3): 92-99. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240039

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The poor mechanical properties of W-Ni₃Al-Co alloy limited its further application in kinetic energy penetrator. The W-(9-x)Ni₃Al-Co-xCeO₂(0.1%, 0.2%, 0.3%, 0.4%) alloys were prepared by the ball-milling and spark plasma sintering (SPS), and the inner relationship between the added CeO₂ content and the relative density, phase, microstructure, and mechanical properties of sintered alloys were analyzed. The results show that the trace added nano-CeO₂ provids the heterogeneous nucleation point for the in-situ formed Al₂O₃, promoting the generation of the in-situ Al₂O₃. The addition of 0.1% CeO₂ does not agglomerate during the sintering process and improves the interfacial bonding strength of the sintered alloy. Meanwhile, the 0.1 w% added nano CeO₂ and in-situ endogenous Al₂O₃ particles synergistically strengthenes the alloy. Finally, the W-8.9Ni₃Al-1Co-0.1CeO₂ alloy showes the outstanding comprehensive properties, its bending strength, hardness, relative density, and tungsten grains were 1 686.67 MPa, 71.14 HRA, 99.53%, and 3.85 μm, respectively.
• Select
  Effect of Y₂O₃ content on microstructure and properties of brass-nickel base alloy by laser additive repairing

  FAN Zhao, HU Jiaqi, ZHANG Zhiqiang, LIU Qingwei

  Powder Metallurgy Industry. 2025, 35(3): 100-106. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240056

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Nickel base alloy powder containing Y₂O₃ rare earth oxide was used for laser additive repair of brass, the effects of different contents of Y₂O₃ rare earth oxide nickel base alloy powder on the microstructure and properties of repaired specimens were studied.The results show that the cladding joint is composed of matrix,heat affected zone and cladding zone.The microstructure of the cladding zone is mainly composed of γ matrix phase, γ'strengthening phase MC phase and Laves phase.With the addition of appropriate amount of Y₂O₃, the microstructure and morphology of the cladding joint are improved and the formation of Laves phase in the cladding zone is effectively restrained,and the segregation of Nb elements between dendrites is improved. The dendritic structure is mainly distributed at the top and middle and lower part of the cladding zone, and the distribution is more compact, and the grain size is also improved. At the same time, the size of precipitated phase in the cladding zone is also significantly reduced. The wear amount of cladding zone decreases at first and then increases with the increase of Y₂O₃ rare earth oxide content. Under the condition of 0.8% Y₂O₃, the wear resistance is the best, and the wear mechanism is abrasive wear.
• Select
  Numerical simulation of gas flow field in electrode induction melting gas atomization process

  FENG Shan, ZHANG Hao

  Powder Metallurgy Industry. 2025, 35(3): 107-114. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240009

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The gas flow field of electrode-induced melting gas atomization technology was simulated using the FLUENT software for fluid dynamics. The influence of supersonic nozzle on different inlet pressures (2, 3, 4 MPa), angles (40°, 45°, 50°), and distances (12, 18, 22 mm) between the supersonic nozzle outlet and metal flow were analyzed. The results indicate that the gas flow field exhibits a series of expansion wave and compression wave jet structures. Increasing the injection pressure effectively enhances the velocity of the gas jet and theoretically generates greater shear force to facilitate atomization. Proper adjustment of the nozzle angle minimizes pressure loss between the gas and pipe wall while controlling the position of the return gas field. Additionally, the distance between nozzle outlet and metal liquid flow affects the location of reflux gas field. As this distance increases, there is a gradual reduction in speed as well as convergence into reflux gas field before being far away from nozzle outlet. If reflux gas field is near center hole (liquid flow down channel) of nozzle, it hinders downward liquid flow leading to reverse injection and splashing. Conversely, if return gas field is far from center hole of nozzle, insufficient atomization occurs resulting in coarse powder particles with irregular shapes.
• Select
  Preparation of FeCoNi magnetic alloy powders

  HAN Sen, QIN Sisi, LIU Donghua, XIAO Mingqing, ZHONG Tao, XIONG Aihu

  Powder Metallurgy Industry. 2025, 35(3): 115-118. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240079

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The ternary soft magnetic alloy powder for magnetic powder clutch-FeCoNi was prepared by Vacuum Gas Atomization. The micromorphology, impurity content and soft magnetic properties of the FeCoNi powder were characterized. The effect of particle size ratio on powder fluidity and apparent density were studied. At the same time, the effect of heat treatment on soft magnetic properties of powder was also researched. The results show that the alloy powder with good fluidity and apparent density can be obtained by selecting the appropriate particle size ratio, When the particle size ratio is 60% (65-105) + 30% (38-65) +10% (28-38), the fluidity of the magnetic powder is 17.09 s/50g and the bulk density is 4.59 g/cm³, which is conducive to improving the performance of the magnetic powder clutch. Through thermal stability analysis, after heat treatment at 800 ℃ for 40 minutes, the coercive force decreased from 10.33 kA/m to 0.58 kA/m, the soft magnetic properties could be significantly improved.
• Select
  Key influencing factors of reduction process on oxygen removal capability in Tantalum powder

  LI Lijun, LIN Fukun, LI Zhenglong, YANG ning

  Powder Metallurgy Industry. 2025, 35(3): 119-124. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240040

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  The properties of tantalum powder with different Mg content, temperature, vacuum time after oxygen reduction and pickling were compared and analyzed, the physical, chemical and electrical properties of tantalum powder under different processing conditions were emphatically analyzed. The results show that the low content of magnesium will lead to high oxygen and magnesium content and high leakage current,the amount of magnesium added in the production process needs to be higher than the theoretical value. As the temperature increases, the volume shrinkage of the product significantly decreases. If the temperature is above 880 ℃,the volume shrinkage is significant. The production process temperature should be controlled below 880 ℃. When the evacuation time is set between 3-5 h, reducing the liquid-solid sintering time and increasing the gas-solid reaction time can significantly lower the leakage current and power loss of the product. The production process should be designed with reasonable processes to reduce the leakage current loss of the product.
• Select
  The microstructure and wear resistance of 18Ni300 steel by laser cladding on stainless steel surface of logistics box

  CHEN Shuang, SHUN Shuzheng

  Powder Metallurgy Industry. 2025, 35(3): 125-130. https://doi.org/10.13228/j.boyuan.issn1006-6543.20230165

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  In order to improve the surface hardness and wear resistance of 304 stainless steel used in logistics tank, 18Ni300 martensitic steel coating was prepared on the surface of 304 stainless steel by laser cladding technology, to improve its service life. The microstructure, phase composition and crystallographic properties of the coating were studied by metallographic microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Electron Backscatter Diffraction (EBSD). The surface microhardness and wear resistance of the coating were tested. The results show that 18Ni300 martensitic steel coating has good formability and no obvious cracks. The phase composition of cladding layer is composed of martensite and austenite, and has high dislocation density. The surface microhardness of 18Ni300 martensitic steel coating is about (408±15.2) HV, which is about twice that of 304 stainless steel. The friction coefficient of 18Ni300 martensitic steel coating is 0.44, the specific wear rate is 4.35×10^-5 mm³/N·m, and the wear mechanism is mainly abrasive wear.
Review and Progress
• Select
  Recent progress in the preparation and properties of metallic Rhenium

  CHEN Fuge, LIU Jie, SHEN Kunrui, KANG Julei, ZHAO Hongchun, LI Xindong, DONG Haihong

  Powder Metallurgy Industry. 2025, 35(3): 131-138. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240065

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Because of its high hardness, high strength, good plasticity and excellent heat shock resistance and creep resistance, rhenium metal has been widely used in aerospace nuclear industry, catalysis field, electronics field, biomedicine and other high-tech fields. In this paper, the preparation methods of rhenium powder and rhenium products are reviewed, among which the hydrogen reduction method is the most popular. The preparation of rhenium powder is developing in the direction of increasing the purity of rhenium powder. The mature preparation methods of rhenium products include powder metallurgy, electron beam melting and chemical vapor deposition. The production cost of powder metallurgy is low, but the production of complex components is difficult. The purity of the product prepared by electron beam melting is high, but the cost is high and the production of complex components is difficult. Chemical vapor deposition method has high purity and can prepare complex components. It is often used for the preparation of thin film materials, but the cost is high. The three methods are relatively mature, and all have certain industrial production capacity. On this basis, the mechanical properties and creep properties of rhenium prepared by different methods are compared. It is concluded that rhenium prepared by hot isostatic pressing and chemical vapor deposition has better properties. However, hot isostatic pressing method has not been industrialized because of its high cost. Domestic research institutions also need to further explore advanced preparation technology, in-depth study of rhenium deformation mechanism, and explore new application fields.
• Select
  Mechanism and research progress of SiC-reinforced magnesium matrix composites

  QIN Qin, LIU Jiawei, WANG Shengqi, ZHANG Yu, ZHANG Shuyi, LI Zhenglong

  Powder Metallurgy Industry. 2025, 35(3): 139-148. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240030

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Magnesium matrix composites are widely used in various industries and have been studied in depth because of their excellent comprehensive properties, such as low density, high specific strength and high specific modulus. This paper mainly reviews the reinforcement mechanism and research progress of SiC on magnesium matrix composites, and finds that SiC can effectively balance the contradictory relationship between strength and plasticity in traditional magnesium matrix composites, and play a good reinforcing effect on magnesium matrix composites. Through the review and analysis, SiC on magnesium matrix composites reinforcement mainly has Orawan strengthening, fine grain strengthening, thermal mismatch strengthening and load transfer strengthening. Meanwhile, the size and distribution of reinforcing particles play a decisive role in strengthening magnesium alloys and determine the strengthening mechanism. For most magnesium alloys, an optimal effect is achieved when the addition of particulate reinforcement is 1 wt%. SiC particles at micro- and nano-scales are more effective in enhancing the mechanical properties of magnesium matrix composites. To achieve high-performance SiC-reinforced magnesium matrix composites, the current optimal methods include melt infiltration, powder metallurgy, stir casting, and high-energy ultrasonic processing. The application of nano-SiC reinforcements in magnesium matrix composites represents a cutting-edge research topic. Through meticulous design and fabrication, it is expected to enhance the mechanical properties, wear resistance, and corrosion resistance of magnesium matrix composites, thus holding broad application prospects in fields such as aerospace, automotive, and electronics.
Innovation and Communication
• Select
  Cu modification for improving the interfacial stability of the solid-state Li batteries

  YOU Zhiping, MA Hong, ZHAO ming

  Powder Metallurgy Industry. 2025, 35(3): 149-155. https://doi.org/10.13228/j.boyuan.issn1006-6543.20240033

  Abstract ( ) Download PDF ( )   Knowledge map   Save

  Solid metal lithium battery is expected to achieve a high energy density of 500 Wh/kg, which is regarded as the key electrochemical energy storage system to achieve a breakthrough in the driving range for new energy vehicles. However, the poor contact stability between the metal Li anode and the solid electrolyte seriously restricts its cycling performance. In this study, the interfacial stability was modified in the aspect of the volume strain of the interphase between the solid electrolyte and Li anode. Different from the conventional modification strategy with high electrochemical activity interphase, a copper film modified layer with low electrochemical activity between the solid electrolyte and the Li anode is introduced, so that the volume change ratio of the interface phase can be greatly reduced, thus enhancing the stability of the interface contact and improving the cycle stability of the solid lithium metal battery. According to the electrochemical impedance spectroscopy, it is found that the area specific resistance of the anode interface is reduced from 2 030 Ω/cm to 65 Ω/cm by the introduction of copper thin film. The gram capacity of lithium cobalt oxide cathode is increased from 118 to 145 mAh/g. Moreover, the capacity retention of the solid-state lithium battery at 0.33 C after 500 cycles is increased from 46.3% to 93.5%.