Improvement of interfacial interaction and mechanical properties in copper matrix composites reinforced with copper coated carbon nanotubes

The incorporation of low-dimensional nanofillers into 3D metal matrix is promising to translate their excellent properties from nanoscale to the macroscopic world. However, the design of firm nanocarbons and efficacious fabrication of such advanced composites remain challenging. In this paper, we report an optimized strategy of carbon nanotubes (CNTs) for reinforcing copper by combining the use of electroless deposition (ED), spark plasma sintering (SPS) and hot-rolling. We finished a perfect match of enhanced yield strength, high plasticity, and good electrical conductivity (e.g. 264 MPa, 29%, 96.6% IACS for 1 vol% CNTs/Cu) in 3D bulks, which is attributed to inherent properties and strong interfacial bonding. In addition, the particularly aligned arrays of CNTs contributed to the transfer stress from the matrix without sacrificing ductility and conductivity. We revealed the strengthening and toughening mechanisms of CNTs in the CNTs/Cu composite through the dislocation theory. This study provides a new approach for the designing and fabricating of novel low-dimensional nanomaterials into 3D metal matrix.