THIN SOLID FILMS
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2024
·
IF 2
Chenlong Wei,Xuexiang Wang,Jun Wen,Qiang Wang,Zhaoshi Donga
A tungsten coating was formed by the in situ reaction of tungsten trioxide formed by the thermal decomposition of ammonium metatungstate in a molten salt (NaCl+BaCl 2 ) environment with carbon atoms on the surface of diamond. Meanwhile, diamond/copper composites were prepared using the prepared tungsten-coated diamonds. The morphology and composition of the coatings and diamond/copper composites were observed using scanning electron microscopy, transmission electron microscopy, and energy-dispersive spectroscopy. The results revealed that the originally smooth diamond surface was uniformly covered by a tungsten coating after low-temperature salt bath treatment at 1050 °C, a temperature 50–100 °C lower than that of traditional methods. Compared to the directly added tungsten trioxide, the tungsten trioxide produced by the thermal decomposition of ammonium metatungstate was more active, and the coating was more uniform. The bending strength and thermal conductivity of tungsten-coated diamond/copper composites were 280.6 MPa and 516 W/(m·k), respectively, which were significantly higher than those of uncoated diamond/copper composites (128.6 MPa and 168 W/m·K). This indirectly confirms that the diamond surface coating can improve the interfacial bonding performance between diamond and copper.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Xiaozhen Wang,Yishi Su,Qiubao Ouyang,Di Zhang
With the rapid development of the miniaturization and high-integration of electronic devices, conventional thermal conductive materials cannot ensure the safety and reliability of the high-power devices in working environments. It is urgent to develop thermal management materials with excellent thermophysical and mechanical properties . In this work, the tungsten-coated graphite flakes (GFs(W)) were prepared by the immersion reduction, and the GFs(W) reinforced copper matrix composites (GFs(W)/Cu composites) were prepared by the vacuum hot-pressing sintering. Based on the microstructure and surface analysis, the W coating obtained at 900 °C and 200 g/L AMT appears the excellent surface structure and interfacial adhesion, which transfer the interfacial bonding from mechanical combination to mechanical-metallurgical synergy between the GFs and Cu. In addition, the volume fraction of W coating has a threshold to improve properties of the GFs(W)/Cu composites, in which the GFs(6 W)/Cu composites show the outstanding comprehensive performance: the in-plane thermal conductivity and flexural strength are 879.0 ± 10.0 Wm −1 K −1 and 166.9 ± 3.4 MPa respectively, which are improved by 22.3% and 356.0%, and the lowest coefficient of thermal expansion is 4.3 ± 0.5 ppmK −1 . To sum up, it provides an effective way to develop novel structural and functional integrated graphite/copper composites for thermal management.
研究领域:
材料科学
·
热管理材料
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Bo Liu,Siming Yan,Yi He,Teng He,Yahui He,Ruxia Song,Zhifei Zhang,Hongjie Li,Jinxue Song,Zhiyuan Li
In this work, with the help of pulsed electrodeposition technology, Ni–W/ZrPP composite coatings on carbon steel surfaces were fabricated. The enhancing effects of inorganic layered alpha-zirconium phosphate (αZrP) and organic zirconium phenylphosphonate (ZrPP) on the surface morphology, microhardness, wear resistance and corrosion resistance of Ni–W coatings were also investigated. The result shows, Ni–W/ZrPP composite coating exhibits the most complete and dense surface morphology without any pinholes and generation of microcracks. Furthermore, the embedding of ZrPP also maximizes the wear and corrosion resistance of the Ni–W coating. This can be reflected by the fact that the Ni–W/ZrPP composite coating has the shallowest and narrowest wear section and the lowest average friction coefficient (0.312). In 3.5 wt.%NaCl solution, the Ni–W/ZrPP composite coating has the highest corrosion potential (E corr = −0.28 V) and the lowest corrosion current density (i corr = 2.3 μA cm −2 ), which show the best corrosion resistance. Relevant mechanistic studies have proven that embedding ZrPP with larger interlayer spacing in the coating is beneficial to promote the interlayer slip of 2D materials and to from frictional transfer films. The hydrophobic group and lamellar structure at the end of ZrPP are also contributors to build a physical barrier and prevent corrosive media from entering the coating.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 6
·1-12
·
IF 2.5
Wang Jiatai,Fan Chao,Li Yuanyuan,Wang Yan,Yan Xiaocen,Deng Changjuan,Li Jian
LiNi 0.815 Co 0.15 Al 0.035 O 2 (NCA) has attracted a lot of attention owing to its high specific capacity and low cost. The problems of capacity loss and interface side reaction during the long cycle hinder the application of NCA cathode materials. In this work, WO 3 -coated LiNi 0.815 Co 0.15 Al 0.035 O 2 cathode materials were successfully prepared, which greatly improved the electrochemical properties of the NCA. Results of XRD show that the WO 3 coating has no significant effect on the structure of the NCA samples. Results of XPS show that WO 3 coating is beneficial to reduce the content of residual alkali substance on the surface of the NCA. In addition, the first discharge specific capacity of NCA@2wt%WO 3 is 174.96 mAh g − 1 at a current density of 1.0 C, with a capacity retention rate of 89.94% after 200 cycles. The discharge specific capacity of NCA@2wt%WO 3 is 137.74 mAh g − 1 at 5.0 C. The coating of WO 3 effectively improves the electrochemical performance of NCA cathode materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2019
·Vol. 50
·期 7
·3301-3309
·
IF 1.985
Xiong Z. H.,Yang Y. F.,Kondoh K.,Misra R. D. K.
A uniform core–shell-structured W-coated Al powder was efficiently prepared by using fluidized bed chemical vapor deposition. The deposited W prevented the defluidization of Al powder and thereby enabled the controlled preparation of core–shell powder with different W-contents. Both the shell and activated sintering of the deposited nano-sized W particles contributed to the formation of a network W-skeleton in the composite. Compared with the W particles and/or aggregates formed from the powder mixture, the formation of W-skeleton which has better interface bonding with the Al matrix may create an excellent and continuous seepage pathway for electrons, resulting in superior electrical conductivity. In addition, the uniform W-skeleton structure led to enhanced tensile strength but a lower ductility. However, the negative response of continuous W-skeleton to the ductility can be ignored when the width of W-skeleton was in the 200 to 300 nm range. The W-content was optimized at 5 wt pct to obtain a good combination of mechanical properties and electrical conductivity.
研究领域:
材料科学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2015
·
IF 4.504
Xinhe Yang,Zicheng Zuo,Haiyan Wang,Quanbin Chen,Hui Zhang,Zhenlei Huang,Borong Wu,Henghui Zhou
A one-step synthesis method is developed to prepare the Li[Ni 0.5 Co 0.2 Mn 0.3 ]O 2 (NCM 523) cathode with uniform tungsten-coating layer for lithium-ion battery . Such modified material shows similar properties with the bare NCM 523 in terms of the primary particles, secondary structure , and specific capacity. With W coating layer , the NCM 523 gives remarkable improvement in the long-term capacity retention in the half-cell testing, which is sharply inconsistent with the result from the full-battery tests, indicating a contradiction between the half-cell and full-battery tests in some case. After further investigations, such conflict between the half-cell and full-cell tests in evaluating the W-coating strategy is attributed to the dissolution of Li 2 WO 4 layer in the electrolyte, which probably destroys the solid electrolyte interface (SEI) on the graphite anode and irreversibly consumes the active lithium ions for renovating SEI in full-cell testing. These results will benefit researchers in the area of lithium-ion batteries to fully understand the differences between the half-cell and full-cell testing, and develop the effective strategies for cathode modifications.
研究领域:
电化学
·
材料科学
·
能源存储
·
电池技术
·
表面改性
·
固态离子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）