Processing and Electrical Properties of Nano-Al2O3/Cu Composites

Copper matrix composites (CMCs) are widely used in electrical equipment and electrical contact materials due to their excellent electrical properties. Al2O3 powders are widely used as a reinforcing agent to enhance mechanical properties of MMCs. The xAl2O3/Cu (x =0, 0.2, 0.5, 0.7, and 1.0wt. %) composites were prepared via vacuum arc melting method. The mechanical and electrical properties were obtained by measuring the hardness and conductivity. The morphology of copper and Al2O3/Cu composites was characterized by optical microscopy (OM) and scanning electron microscopy (SEM). With the addition of Al2O3 from 0.2 wt. % to 1.0 wt. %, the relative densities of composites decreased from 98.5% to 97.0%. The hardness of the composites increased with increase in the Al2O3 powders content. The hardness of 1.0Al2O3/Cu composites was 57.9 HB, which was higher than that of pure Cu by 18.6%.. With the addition of Al2O3, the IACS% of Al2O3/Cu composites decreased from 88.97 to 86.16.

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High Oxidation Resistance of CVD Graphene-Reinforced Copper Matrix Composites

Nanomaterials ◽

10.3390/nano9040498 ◽

2019 ◽

Vol 9 (4) ◽

pp. 498 ◽

Cited By ~ 3

Author(s):

Mingliang Wu ◽

Baosen Hou ◽

Shengcheng Shu ◽

Ao Li ◽

Qi Geng ◽

...

Keyword(s):

Powder Metallurgy ◽

Oxidation Resistance ◽

Electrical Contact ◽

Chemical Vapor ◽

Surface Oxidation ◽

Copper Matrix ◽

Contact Materials ◽

Graphene Layers ◽

Electrical Contact Materials ◽

Pure Cu

Copper-based materials are common industrial products which have been broadly applied to the fields of powder metallurgy, electrical contact, and heat exchangers, etc. However, the ease of surface oxidation limits the durability and effectiveness of copper-based components. Here, we have developed a powder metallurgy process to fabricate graphene/copper composites using copper powders which were first deposited with graphene layers by thermal chemical vapor deposition (CVD). The graphene/copper composites embedded with an interconnected graphene network was then able to be obtained by vacuum hot-pressing. After thermal oxidation (up to 220 °C) in humid air for several hours, we found that the degree of surface oxidation of our samples was much less than that of their pure Cu counterpart and our samples produced a much smaller increase of interfacial contact resistance when used as electrical contact materials. As a result, our graphene/copper composites showed a significant enhancement of oxidation resistance ability (≈5.6 times) compared to their pure Cu counterpart, thus offering potential applications as novel electrical contact materials.

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High-temperature mechanical and electrical properties of W-particle-reinforced Cu-matrix composites from improved electroless plated powders

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/09544062jmes1343 ◽

2009 ◽

Vol 223 (6) ◽

pp. 1285-1295 ◽

Cited By ~ 3

Author(s):

T-T Liao ◽

C Kung

Keyword(s):

Electrical Properties ◽

Electrical Contact ◽

Tungsten Particle ◽

Matrix Composites ◽

Composite Powders ◽

Diverse Range ◽

Mechanical And Electrical Properties ◽

Standard Powder ◽

Pure Cu ◽

Composite Samples

Copper (Cu)-matrix composites combine the high electrical and thermal conductivities of Cu with the enhanced wear resistance and strength of the reinforcement material, and are therefore widely used for electrical contact applications in a diverse range of fields. In the current study, tungsten-reinforced copper (W—Cu) composite powders are fabricated using a novel electroless Cu plating process in which the homogeneity of the powder mixture is improved via the use of an ultrasonic agitation technique. The volume content of the tungsten particle reinforcement in the composite specimens is 3, 6, and 12 per cent, respectively, and standard powder metallurgical techniques are then applied to produce the final composite powders. The mechanical and electrical properties of the composite powders are evaluated at room temperature and at temperatures ranging from 100 to 300 °C. Fracture surfaces of the composite samples are ana-lysed using scanning electron microscopy. The results show that the mechanical properties of the W—Cu composite samples are significantly better than those of pure Cu specimens, particularly at higher temperatures. Furthermore, the addition of 3 vol% W particles to the W—Cu composite is found to yield a reduction of not more than 2 per cent in the electrical conductivity of the composite sample compared to that of a pure Cu specimen. Overall, the results indicate that the optimal mechanical and electrical properties are obtained by mixing pure Cu powder with 3 vol% of Cu-plated W particles with a mean dimension of 1 μm.

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Enhanced mechanical and electrical properties of novel graphene reinforced copper matrix composites

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2018.10.357 ◽

2019 ◽

Vol 777 ◽

pp. 309-316 ◽

Cited By ~ 24

Author(s):

C. Salvo ◽

R.V. Mangalaraja ◽

R. Udayabashkar ◽

M. Lopez ◽

C. Aguilar

Keyword(s):

Electrical Properties ◽

Copper Matrix ◽

Matrix Composites ◽

Copper Matrix Composites ◽

Mechanical And Electrical Properties

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Study on Ag/SnO2/TiO2 Electrical Contact Materials Prepared by Liquid Phase In Situ Chemical Route

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.936.486 ◽

2014 ◽

Vol 936 ◽

pp. 486-490 ◽

Cited By ~ 3

Author(s):

Yan Cai Zhu ◽

Jing Qin Wang ◽

Li Qiang An ◽

Hai Tao Wang

Keyword(s):

Liquid Phase ◽

Electrical Properties ◽

Electrical Contact ◽

Electrical Performance ◽

Powder Metallurgy Method ◽

Chemical Route ◽

Contact Materials ◽

Electrical Contact Materials ◽

Distribution State

In order to improve the machinability and electrical performance of the Ag electrical contact materials. A new kind of nano-Ag/SnO2-TiO2 electrical contact materials were prepared by liquid phase in-situ chemical route. The distribution state of elements titanium in copper and their effects on the microstructures and properties have been studied. The results of SEM show that SnO2-TiO2 powders are small, uniform and with no obvious phenomenon of reunion. At last, Ag/SnO2-TiO2 electrical contact materials were prepared by powder metallurgy method and electrical performance were done. Test results show that the electrical properties of Ag/SnO2-TiO2 are superior to the electrical properties of Ag/SnO2. Hence Ag/SnO2-TiO2 may become a new contact material which can replace Ag/SnO2.

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Fabrication of SiC@Cu/Cu Composites with the Addition of SiC@Cu Powder by Magnetron Sputtering

International Journal of Photoenergy ◽

10.1155/2021/6623776 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Zhang Yunlong ◽

Li Wenbo ◽

Hu Ming ◽

Yi Hongyong ◽

Zhou Wei ◽

...

Keyword(s):

Magnetron Sputtering ◽

Relative Density ◽

Vickers Hardness ◽

Surface Engineering ◽

Coefficient Of Thermal Expansion ◽

Electrical Contact ◽

Engineering Application ◽

Copper Matrix ◽

Contact Materials ◽

Electrical Contact Materials

In view of the surface engineering application of electrical contact materials, SiC ceramic particles were introduced into copper matrix composites by the hot-press sintering method for the sake of enhancing the service life of copper matrix electrical contact materials. Magnetron sputtering technology was exploited to form the continuous copper film on the β-SiC powders in order to improve interface wettability between SiC powder and copper matrix. The SiC@Cu powders were treated by magnetron sputtering technology. Then, dynamic deposit behavior was described according to SEM results. The phase constitution, fracture morphology, relative density, porosity, Vickers hardness, and coefficient of thermal expansion of SiC@Cu/Cu composites with different SiC@Cu addition were analyzed in detail. The results showed that SiC@Cu powders with higher fraction in the SiC@Cu/Cu composites would decrease relative density and increase porosity, so it resulted in improvement of Vickers hardness. The addition of SiC@Cu decreased CTE values of the SiC@Cu/Cu composite, especially at high-level fraction SiC@Cu powder.

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