Simultaneous achievement of high strength, excellent ductility, and good electrical conductivity in carbon nanotube/copper composites

In this study, a novel mixing method that combines wet mixing and conventional ball milling followed by spark plasma sintering (SPS) was used to fabricate carbon nanotube (CNT)-reinforced Cu-matrix composites. The samples were characterized using scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and X-ray diffraction. In the CNT/Cu composites produced, the CNTs were uniformly dispersed whilst maintaining their integrity. Consequently, a combination of high strength, ductility, and electrical conductivity was achieved by a 2.5 vol% CNT/Cu composites (ultimate tensile strength 280 MPa, elongation 41.7%, and electrical conductivity (IACS%) 91.6%). These results could potentially be used to effectively ameliorate the issue of strength-ductility and strength-conductivity trade-offs in metal-matrix composites.