Fabrication, characterization, and mechanical properties and wear characteristics of graphite nanoplatelets incorporated nanotwinned Cu composites

Abstract

The present research is focused on the study of microstructural evolution and mechanical behaviour of graphite nanoplatelet (xGnP, where x = multiple layers of graphene) (a graphene isotope) incorporated Cu composites. The limited excellence of Cu in the mechanical field is enhanced by the incorporation of xGnP nanoreinforcement. A dispersion extent of nanoplatelets over the matrix via ultrasonication is reported. The ex-situ fabrication is carried out through powder metallurgy followed by particle fusion via furnace sintering and spark plasma (SP) sintering. Results of characterization showed the homogeneous distribution of graphite nanoplatelet throughout the Cu matrix at lower graphite nanoplatelet loading concentrations. It is also recognized that both furnace sintered and SP sintered Cu composites showed a remarkable enhancement in mechanical properties and wear behaviour with respect to that of similarly fabricated monolithic pure Cu samples. Cu twins are evident in the optical micrographs. The higher incorporation concentration of the graphite nanoplatelet limits the optimum values thus resulting in the non-uniform distribution of the graphite nanoplatelet, formation of relatively bigger conglomerates, and generation of pores. This in turn limited the mechanical performance at higher graphite nanoplatelet loading concentrations due to uneven hardness, poor densification, formation of cracks, and bigger delamination on the surface during the wear of the samples.