JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 9
·6562-6573
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IF 2.993
Jia Zhengfeng,Li Haoqi,Zhao Yao,Dikin Dmitriy A.,Ni Junjie,Zhao Limin,Zhen Jinming,Ge Bo,Shao Xin,Ren Fei
In this study, copper (Cu)/polydopamine (PDA) composite was fabricated by vacuum hot-press sintering of micrometer-sized Cu particles covered with PDA film tailored at the nanometer scale thickness. The resultant compacts exhibited much higher electrical conductivity than the uncoated counterparts. Analyses of sintered samples using scanning and transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy revealed the conversion of PDA into carbonized PDA (cPDA). The increased mass density and grain growth are likely responsible for improved electrical conductivity of the composite material.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2022
·
IF 7.305
Nan Sheng,Yunfei Ge,Yunqi Guo,Chunyu Zhu,Zhonghao Rao
This study reports the successful fabrication of Cu@Al 2 O 3 macro-encapsulated metallic PCMs for high-temperature thermal storage over 1000 °C. Cu powders are employed as raw material which are spherulitized to core balls in millimeter-size, and subsequently the core balls are cladded with Al 2 O 3 ceramic shells. After the low-temperature pre-sintering and subsequent high-temperature sintering treatment, the Cu@Al 2 O 3 macrocapsules which contain gaps between the shells and cores are successfully prepared. The core balls are consisted of Cu powders which are not densified but are porous, offering buffer spaces to accommodate the thermal volume expansion during high-temperature sintering and melting of Cu. As a comparison, Cu@Al 2 O 3 macrocapsules prepared by directly coating the commercial solid Cu balls are leaky. Thermal analysis indicates that the metallic core PCM has a melting temperature of 1063 °C and a latent heat of around 210 J/g. The macrocapsules are also highly durable as confirmed by the melting-solidification cycling test. These results demonstrate that the Cu@Al 2 O 3 macrocapsules are applicable as high-temperature heat storage media, which can find useable applications in advanced high-temperature thermal energy storage systems .
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2018
·
IF 2.943
Kewei Li,Fei Gao
The heterogeneity of grain refinement and texture formation in conductive copper powder during pulsed electric current sintering have been investigated by means of microstructural analysis of the particle-contacting zone of the samples sintered with micron-sized powders. The particle-contacting region was indicated to experience a higher level of grain refinement than the particle center due to the inhomogeneous temperature distribution among the particle when pulsed electric current passed through. Meanwhile, two main textures of Cube (1 0 0)[0 0 1] texture and Goss (1 1 0)[0 0 1] texture were directly detected in the sintered Cu samples by a combination of electron backscatter diffraction and X-ray diffraction. Based on the experimental results, a feasible mechanism for the formation of texture during the pulsed electric current sintering has been proposed by considering the applied uniaxial pressure and pulsed electric current as well as the rearrangement of grains. In addition, the effects of heterogeneous grain refinement and texture formation on the tensile properties of the sintered Cu samples were also discussed based on the tensile properties and fractographic. These results would contribute to the basic understanding of the sintering mechanisms in pulsed electric current sintering process.
研究领域:
材料科学
·
金属学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2013
·Vol. 24
·期 12
·4913-4918
·
IF 1.486
Wu Min,Lin Baoping,Cao Yi,Song Jiangang,Sun Ying,Yang Hong,Zhang Xueqin
In this paper, uniform and well dispersed silver-coated copper powders were prepared by replacing reaction at first. The structure and properties of the bimetallic powders were investigated by XRD, SEM and TGA. It was found that anti-oxidization of the silver-coated copper powders increased with the increase of the silver content slightly and a dense coating surface was observed at Ag content of 53.9 wt%. Furthermore, the pastes with relatively low silver content which were prepared from silver-coated copper powders, displayed high conductivity similar to pure silver even after sintering in air. And their sintering properties were also investigated at different temperature in air atmosphere. The film exhibits good electrical properties at sintering temperature between 800 and 900 °C. When the paste from silver-coated copper powder with Ag content of 53.9 wt% was printed on Al 2 O 3 substrate and sintered at 800 °C in air, the sheet resistance of the film is 0.036 Ω/□ only.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2025
·
IF 6.1
Jiaxing Li,Jiongming Chen,Ying Chen,Jialei Ren,Jianan Li,Liankui Wu,Hongwei Liu,Fahe Cao,Qingqing Sun
This study develops a new shot peening method, i.e., copper powder ultrasonic shot peening, and investigates its antibiofouling effect on commercially pure titanium grade 2 (TA2) alloy in seawater. The results indicate that adding Cu powder during ultrasonic shot peening can form a Cu-containing layer with a thickness 1–2 μm on the surface of TA2 alloy, primarily in the form of nanocrystals. This Cu-containing layer exhibits a 90 % antifouling efficiency against Pseudomonas aeruginosa and an 85 % efficiency against Aspergillus terreus , mainly due to the release of Cu ions during immersion. Electrochemical corrosion test results show that corrosion rate of this anti-fouling layer is two orders of magnitude higher than the substrate alloy, which significantly enhances the release of Cu ions and thereby improving the antifouling capability. Tensile test results show that Cu powder peening similarly improves the mechanical properties of TA2 alloy as conventional peening.
研究领域:
材料科学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
An Wang,Kanggen Zhou,Xuekai Zhang,Dingcan Zhou,Changhong Peng,Wei Chen
Large amounts of waste acids with high acidity and arsenic levels are produced during pyrometallurgy of nonferrous metal sulfide ores, in which the treatment of arsenic remains a problem. In this study, copper powder was used as a reducing agent and synergized with iodine ions to effectively remove arsenic from waste acids. The influences of stirring speed, copper powder particle size, sodium iodide/copper powder dosages, and reaction temperature on the removal efficiency of arsenic were investigated. The results showed almost complete removal of arsenic under the optimal conditions: 600 rpm stirring speed, copper powder particle size <15 μm, molar ratio I:As = 5, molar ratio Cu:As = 8, reaction temperature 40 °C, and reaction time 90 min. The kinetics studies indicated that arsenic removal was controlled by chemical reaction with apparent activation energy of 42.39 kJ·mol −1 . The morphological and structural characterizations of dearsenization residues showed surface of copper particles with double covering-layers. The interior covering-layer constituted the formation region of As(0), the phases of which were As and As-Cu intermetallic compounds, while the main product formed in exterior covering-layer was identified as CuI.
研究领域:
环境科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL PAPERS
·
2020
·Vol. 74
·期 7
·2123-2131
·
IF 1.68
Zhai Xueying,Guo Jingdong,Zhang Wenshu,Yang De’an
In this study, the zeta potential on the surface of copper powder was adjusted by changing the pH value and adding cetyltrimethylammonium bromide (CTAB). Silica sol was coated directly on copper powder through physical adsorption. The as-prepared SiO 2 -coated copper powders were mixed with organic vehicle and screen printed on low-temperature co-fired ceramic substrate to form copper films. The binder-burn-out process of the films was carried out at 550 °C for 1 h in N 2 /H 2 O atmosphere and then sintered at 910 °C for 1 h in N 2 atmosphere. The results proved that zeta potential had a major effect on the coating morphology of SiO 2 -coated copper powder. The SiO 2 -coated copper powder with a weight ratio of 1% showed a uniform and smooth surface. When the CTAB concentration was 1 × 10 –4 mol/L, the copper powder exhibited the highest zeta potential of 98.2 mV, and the copper film had the best conductivity with a sheet resistance of 1.8 mΩ/□.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale Advances
·
2024
·Vol. 6
·期 4
·1135-1144
·
IF 4.6
Xin Ke,Bingqing Xie,Jingguo Zhang,Jianwei Wang,Weiying Li,Liqing Ban,Qiang Hu,Huijun He,Limin Wang,Zhong Wang
High-purity, monodisperse, and low-oxygen submicron copper powder particles with particle sizes in the range of 100–600 nm were synthesized under alkaline conditions using ascorbic acid (C6H8O6) as a reductant and copper chloride (CuCl2·2H2O) as a copper source. The redox potential of the Cu–Cl–H2O system was obtained by calculations and plotted on pH–E diagrams, and a one-step secondary reduction process (Cu(II) → CuCl(I) → Cu2O(I) → Cu(0)) was proposed to slow down the reaction rate. The commonalities and differences in the nucleation and growth process of copper powders under methionine (Met), hexadecyl trimethyl ammonium bromide (CTAB), and sodium citrate dihydrate (SSC) as protectants and without the addition of protectants are compared, and the reaction mechanism is discussed. Among them, methionine (Met) showed excellent properties and the Cu2O(I) → Cu(0) process was further observed by in situ XRD. The synthesized copper powder particles have higher particle size controllability, dispersibility, antioxidant properties, and stability, and can be decomposed at lower temperatures (<280 °C). The resistivity can reach 21.4 μΩ cm when sintered at a temperature of 325 °C for 30 min. This green and simple synthesis process facilitates industrialization and storage, and the performance meets the requirements of electronic pastes.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HYDROMETALLURGY
·
2019
·
IF 3.465
Yukun Shen,Huibin Zhang,Huazhen Cao,Liankui Wu,Guoqu Zheng
An efficient method for extracting bismuth (Bi 3+ ) from a hydrochloric acid (HCl) system by cementation with copper (Cu 0 ) powder was proposed in this work. The thermodynamic properties of cementation were investigated via cyclic voltammetry measurement and thermodynamic calculation. Then, the effects of reaction temperature, Cu 0 /Bi 3+ molar ratio, stirring rate, HCl concentration, and competing ions on the cementation efficiency of bismuth were systematically investigated. Results showed that the cementation reaction between bismuth and copper powder was thermodynamically spontaneous. A Bi recovery of 99% could be achieved with copper powder under an optimized cementation condition (6 mol L −1 HCl, 60 °C, Cu 0 /Bi 3+ molar ratio of 4, stirring rate of 500 rpm, and reaction time of 30 min). Kinetics study revealed that Cu 0 -Bi 3+ cementation followed a first-order reaction law in the range of 20 °C–60 °C. The activation energy of bismuth cementation was 8.58 kJ mol −1 . The generated cuprous ions can be recovered as copper sulfides by sulfuration after Bi 3+ was extracted. This finding indicated that Cu 0 powder cementation showed potential for Bi 3+ extraction.
研究领域:
化学工程
·
冶金学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2025
·Vol. 60
·期 7
·3392-3407
·
IF 3.9
Wang Xuewen,Zhao Jie,Shi Qingwen,Li Peibo,Luo Guoqiang,Shen Qiang,Sun Yi
Metal electrodes of crystalline silicon solar cells need to possess good photoelectric conversion properties and play a critical role in converting solar energy into electrical energy, making it particularly important to obtain highly conducive, cost-effective and chemically stable materials. This paper prepared uniformly silver-coated copper powders (Cu@Ag) via electroless plating and a conductive film with low sheet resistance by air oxidation combined with hydrogen reduction sintering (jointly referred to as oxidation–reduction sintering). In addition, the densification mechanism of the Cu@Ag conductive film during sintering was revealed. Results showed that oxidation–reduction sintering promoted the diffusion between Cu and Ag, enhancing the plastic flow of phases and improving the densification of the conductive film. Moreover, the densification of the conducive films was further improved by designing multiple layers. The sheet resistance of the four-layer Cu@Ag conductive film was reduced to 1.5 mΩ/□ at 700 °C, while that of the four-layer Cu@Ag conductive film increased by only 0.6 mΩ/□ at 200 °C after eight days, much more stable than Cu film. This work demonstrates the tremendous potential of oxidation-resistant Cu@Ag conductive pastes in low-cost photovoltaic cells, electronics, and other commercial applications. Graphical
研究领域:
材料科学
·
太阳能技术
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
·
2024
·
IF 2.2
Yang Wenqiang,Han Shanyu,Yin Yakun,Wang Zelong,Shi Wen,An Juan,Wang Hongdan,Xia Wentang
The production of ultralight copper powder (UCP) remains challenging due to the requisite ultralow apparent density coupled with a well-developed dendritic morphology, which greatly constrain the modulation and optimization of process parameters. In this study, we conducted a comprehensive investigation to gain deeper insights into the impact of these parameters on the performance of deposited UCPs. Our findings revealed the limitations of relying solely on conventional electrolytic parameters for tailored UCP production. To overcome this challenge, the introduction of hydrochloric acid into the electrolyte system was proposed. Upon which, remarkable improvements in UCP production were observed, including optimized dendritic morphology, enhanced current efficiency and reduced power consumption. By adjusting the amount of chloride addition, UCPs with tunable particle sizes and apparent densities were obtained. Under the benchmark factory process condition, the chloride-treated UCP exhibited an ultralow apparent density (0.47 g cm −3 ) and particle size (19.96 μm), considerably surpassing the corresponding figures for industrial copper powder (1.79 g cm −3 and 64.10 μm) and even the optimum values achieved by GGP Metalpowder AG for their UCP products (0.55 g cm −3 and < 63 μm), with 22.5% of the particles exhibiting simultaneously ultralight and ultrafine properties.
研究领域:
材料科学
·
电化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Jian Zhang,Junkai Chang,Yiming Yin,Jianlong Dai,Yunfei Ge,Bo Zhao,Nan Sheng,Chunyu Zhu
The development of practical high temperature metallic phase change macrocapsules still faces difficulties, because metallic phase change materials undergo volume expansion during phase transformations, which can lead to outer shell rupture. When a core made of stacked metal powders is used, a cavity is eventually formed inside the capsule that acts as a cushion for volume expansion, thus reducing the risk of capsule rupture. However, the cavity will weaken the thermal storage capacity of the capsule, and in order to obtain a capsule with good thermal storage capacity and long-time cycling stability, it is necessary to find a suitable cavity volume of the capsule. In this paper, Cu powders are used as the core raw material, which are spherelized into millimeter level spheres, and the Cu powder spheres are isostatically pressed using an isostatic presser under different pressures to achieve the optimization of the cavity volume by reducing the gap between the powders. The high strength α-Al 2 O 3 is selected as the shell, and sintering additives MgO and SiO 2 are doped into the raw material, and the Cu@MgO-SiO 2 /Al 2 O 3 capsules are prepared after two-step sintering treatment. The material properties and thermal storage properties of the capsules are investigated in detail, which have strong thermal storage properties, for example, in the temperature interval of 1000–1100 ℃, capsules with a core-shell structure (named as [email protected] –100 MPa, prepared with initial diameter of Cu core of 9 mm, shell thickness of 1.5 mm, and isostatic pressing under 100 MPa to the core precursor) exhibit a high heat storage density of 222 J/g and 841 MJ/m³. In addition, we conduct melting-solidification cycle tests, which confirms the excellent durability of the capsules. The comprehensive results show that the Cu@MgO-SiO 2 /Al 2 O 3 macrocapsules possess strong thermal storage capacity and can be used as effective thermal storage materials, especially in advanced high temperature thermal storage systems.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）