A novel Cu-carbon nanotube sheet composite manufactured via the ARB process: A microstructural and mechanical study

Abstract

A Cu matrix composite was designed and produced successfully by adding carbon nanotubes (CNTs) as reinforcement particles. The accumulative roll bonding (ARB) process was used to introduce the material in the shape of the sheet. The process was repeated up to five ARB cycles to obtain a uniform composite with good mechanical properties. Different amounts of CNTs were added to the matrix of Cu in order to evaluate the behavior of the CNTs in the matrix of the Cu. Microstructural evaluations confirmed that by increasing the ARB cycles, a uniform distribution of the CNTs was achieved. However, for Cu-1%CNT considerable numbers of unbonded areas led to weak bonding. Also, the material responded differently to the applied tensile test during loading. For low amounts of CNT-contained composites, the ultimate tensile strength (UTS) was increased in each ARB pass, but, for Cu-1%CNT composite, the UTS was the lowest. Also, microscopy observations were used to study the distribution/configuration of CNTs. The weak bonding of the Cu layers in some spots was attributed to the agglomeration of CNTs between the layers. Fractography of the samples after the tensile test, also, showed remarkable separation between the unbonded layers.