Hierarchical tungsten-copper composite reinforced by a concrete skeleton of particulate and fibrous tungsten with coherent Cr precipitates in the copper matrix

Carbon nanotubes (CNTs) reinforced copper composite powders were fabricated by electrochemical co-deposition. The purification and modification of MWCNTs and the effect of surfactants on deposition process were studied to improve uniform distribution of CNTs in copper matrix and the interfacial adhesion between them. The results indicate that MWCNTs treated by mixture concentrated acid generate many functional groups, such as hydroxyl group and carboxyl group, which greatly improve the hydrophily of CNTs and the co-deposition of CNTs and copper cation in the electrolyte. Further, a good adhesion of CNTs in copper matrix is obtained in the present study as revealed through the micrograph analysis of as-deposited Cu/CNTs composite powders by means of scanning electron microscope (SEM) and transmission electron microscope (TEM).

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Preparation and Properties of Carbon Nanotubes Reinforced Cu Matrix Composites for Electronic Packaging Application

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.1789 ◽

2013 ◽

Vol 275-277 ◽

pp. 1789-1793 ◽

Cited By ~ 1

Author(s):

Long Shan Xu ◽

Xiao Hua Chen ◽

Xing Jun Liu

Keyword(s):

Carbon Nanotubes ◽

Electronic Packaging ◽

Pure Copper ◽

Copper Matrix ◽

Matrix Composites ◽

Composite Powders ◽

Multi Walled Carbon Nanotube ◽

The Matrix ◽

Copper Composite ◽

Copper Nanocomposites

Multi-walled carbon nanotube (MWCNT) reinforced copper nanocomposites were prepared using a unique spherical MWCNT-implanted copper composite powders. The MWCNTs are homogenously ‘locked’ in the composite and tightly bonded to the matrix, which makes them play excellent reinforcement role on the microhardness compared with the unreinforced pure copper. Although the thermal conductivity is not enhanced for the thermal resistance between the carbon nanotubes and the copper matrix; it is still high enough to be used as electronic packaging materials even the concentration of MWCNTS in the composite is up to 5 wt%. Furthermore, the thermal expansion of the composites decreased apparently with the addition of the carbon nanotubes.

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A simple and economical method for the synthesis of steel-reinforced copper composite

Journal of Composite Materials ◽

10.1177/0021998320956390 ◽

2020 ◽

pp. 002199832095639

Author(s):

Feras Kafiah ◽

Jafar Al-Haidary ◽

Sami Masadeh ◽

Emad Abdelsalam ◽

Malek Alkasrawi

Keyword(s):

Brinell Hardness ◽

Copper Matrix ◽

Stir Casting ◽

Compressive Yield Strength ◽

Micro Hardness ◽

Particle Content ◽

The Matrix ◽

Copper Matrix Composite ◽

Steel Particle ◽

Copper Composite

The present study explores a new method of steel particle-reinforced copper matrix composite synthesis. Steel reinforced copper was prepared by stir casting processing method at variable percentages between 10 wt% and 50 wt%. Characterization and mechanical testing were performed on these composites using a variety of techniques. The results showed that the microstructure of the composites has a uniform distribution of steel particles in the matrix with good interfacial integrity. Brinell hardness, tensile and yield strengths, impact energy and compressive yield strength of the composites increased with increasing steel particle contents. Vickers micro-hardness increased markedly at the interface region between particle and matrix evident by the hardness maps. The friction coefficient increased proportionally with increasing steel particle content in the composite, but the contrary was noticed for accumulative wear amount. A slight decrease in deformability is expected by increasing particle content. A ductile fracture was noticed in fractographs of fracture surfaces. Cracks are propagated in the Cu matrix up to the point of fracture, i.e. not through the interfacial boundaries.

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Anisotropic thermal expansion behaviors of copper matrix in β-eucryptite/copper composite

Materials Science and Engineering B ◽

10.1016/j.mseb.2012.03.036 ◽

2012 ◽

Vol 177 (11) ◽

pp. 873-876 ◽

Cited By ~ 2

Author(s):

Lidong Wang ◽

Zongwei Xue ◽

Yingjie Qiao ◽

W.D. Fei

Keyword(s):

Thermal Expansion ◽

Copper Matrix ◽

Anisotropic Thermal Expansion ◽

Copper Composite

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Characterization of Tantalum Carbide Reinforced Copper Composite Developed Using Mechanical Alloying

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.471-472.798 ◽

2011 ◽

Vol 471-472 ◽

pp. 798-803 ◽

Cited By ~ 5

Author(s):

Emee Marina Salleh ◽

Zuhailawati Hussain

Keyword(s):

Milled Powder ◽

Graphite Powder ◽

Copper Matrix ◽

High Energy ◽

Planetary Mill ◽

Tantalum Carbide ◽

Mechanically Alloyed ◽

Consolidation Pressure ◽

Copper Composite

The effects of the consolidation pressure on the properties of novel Cu-15vol% TaC composite was investigated. The copper-based composite has been prepared using a high energy planetary mill via in-situ route. A mixture of copper, tantalum and graphite powder was mechanically alloyed for milling time of 8 hours at speed of 400 rpm. The as-milled powder was consolidated by cold pressing under various pressure (i.e. 100, 200, 300 and 400 MPa) at room temperature and sintered in argon atmosphere at 900 °C for an hour. TaC phase was formed in copper matrix after sintering process. An increase in consolidation pressure resulted in an increase in hardness, electrical conductivity and density of the composites. The changes of bulk properties of the in-situ Cu-TaC composite were correlated to the formation of TaC phase and a reduction of porosity which led to an increasing in densification.

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Properties and Spot Welding Performance of Copper Composite Reinforced with Recycled Tungsten Carbide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.154-155.1485 ◽

2010 ◽

Vol 154-155 ◽

pp. 1485-1488

Author(s):

Zuhailawati Hussain ◽

Indra Putra Almanar

Keyword(s):

Electrical Conductivity ◽

Tungsten Carbide ◽

Spot Welding ◽

Copper Matrix ◽

Raw Material ◽

Composite Electrodes ◽

Welding Operation ◽

Metal Metal ◽

Copper Matrix Composite ◽

Copper Composite

In this work, properties and spot welding performance of copper matrix composite electrode reinforced with 15 vol% tungsten carbide particulate from inexpensive raw material were investigated. Mixture of copper and recycled tungsten carbide was milled, compacted, sintered and powder forged at different pressures. Higher forging pressure resulted in higher density and electrical conductivity as it accelerates the flow of copper matrix leading to porosity elimination and improves metal-metal contact within the copper matrix by reducing porosity and oxide film. Welding operation showed that composite electrodes with higher density, electrical conductivity and hardness forms larger and stronger spot weld.

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Mean and Instantaneous Thermal Expansion of Uncoated and Ti Coated Diamond/Copper Composite Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.702.202 ◽

2013 ◽

Vol 702 ◽

pp. 202-206 ◽

Cited By ~ 3

Author(s):

Qing Yun Wang ◽

Wei Ping Shen ◽

Ming Liang Ma

Keyword(s):

Thermal Expansion ◽

Vapor Deposition ◽

Volume Fraction ◽

Coefficient Of Thermal Expansion ◽

Copper Matrix ◽

Powder Metallurgy Method ◽

Titanium Film ◽

Diamond Particles ◽

Vapor Deposition Technique ◽

Copper Composite

Heat sink materials not only should have higher thermal conductivity, but also have smaller difference of thermal expansion with cooled material. diamond/copper composites were made by the powder metallurgy method. Vacuum slowly vapor deposition technique was employed to deposit a titanium film on diamond particles before mixing with Cu powder in order to improve the bonding strength between Cu and diamond particles during sintering. The thermal expansion of diamond/Cu d composite was measured in the temperature range from 50 to 600 °C. The results show that the titanium film on diamond improves the interfacial bonding and reduces the coefficient of thermal expansion (CTE) of Cu/diamond composites. The CTE of diamond/Cu composites decreases with increasing diamond volume fraction as the results of mixture rule and the intense restriction effect of diamond reinforcement on the copper matrix. The residual stresses and pores in the composites affect instantaneous thermal expansion of diamond/Cu composites.

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Microstructural Development in Nb-Ti Multifilamentary Superconductors During Processing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117911 ◽

1985 ◽

Vol 43 ◽

pp. 190-191

Author(s):

A. W. West

Keyword(s):

Heat Treatment ◽

Critical Current Density ◽

Copper Matrix ◽

Wire Drawing ◽

Heat Treatments ◽

Microstructural Development ◽

Final Size ◽

Density Values ◽

The Wire ◽

Multifilamentary Superconductors

The influence of the filament microstructure on the critical current density values, Jc, of Nb-Ti multifilamentary superconducting composites has been well documented. However the development of these microstructures during composite processing is still under investigation.During manufacture, the multifilamentary composite is given several heat treatments interspersed in the wire-drawing schedule. Typically, these heat treatments are for 5 to 80 hours at temperatures between 523 and 573K. A short heat treatment of approximately 3 hours at 573K is usually given to the wire at final size. Originally this heat treatment was given to soften the copper matrix, but recent work has shown that it can markedly change both the Jc value and microstructure of the composite.

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