Effect of CNTs content on the microstructures and properties of CNTs/Cu composite by microwave sintering

Cu matrix composites reinforced with 0-3 wt% CNTs are fabricated via molecular-level mixing, microwave sintering and rolling technology. A homogeneous distribution of CNTs is exhibited in copper matrix. Clean CNTs/Cu interfaces perform high bonding strength. Electrical conductivity and relative density of microwave sintered CNTs/Cu composites decrease with increase in CNTs content. There exists maximum for hardness of CNTs/Cu composites which rise and then fall with the rise of CNTs content. When CNT contents are less than 1 wt%, it provides a good control over microstructures with low porosity and small pore size. Subsequent rolling process enables better microstructure and performance of sintered composites which shows tensile strength of 218 MPa, the elongation of 37.75%, and the electrical conductivity of >98% IACS compared to pure copper. Our studies provide a robust approach to high-performance CNTs/Cu composites by microwave sintering.