Study On Fabrication, Microstructure And Properties Of Superaligned Carbon Nanotubes Reinforced Copper Matrix Composite

Pure copper materials have been widely used in manufacturing of electric equipment and heat conductor because of their excellent electrical and thermal properties. The use of pure copper, however, is limited by its low strength. Therefore the manufacturing of high strength and high conductivity copper is significant.Carbon nanotubes in superaligned film of carbon nanotubes(SACNT) are all lined up in the same direction. SACNT films are ideal reinforcement for copper to increase strength and keep high conductivity along the direction of CNTs. SACNT/Cu composite was fabricated by electroplating process. We put the SACNT film on a titanium plate and then electroplated a layer of copper on it. By repeating the above process, we could get the laminar Cu/S ACNT composite which contains dozens or hundreds layers of copper and SACNT films. This method which features in simple technology is a potential way to make applicable composites.The results of study indicate that there are large differences between composites fabricated by copper plating solution with the high copper concentration and low acid concentration(high cooper low acid) and high acid low cooper. Composites fabricated by high acid low copper plating solution have features of higher surface roughness. The integrity of SACNT film was broken during electroplating and the bonding at the interface between CNT and copper isn’t well. SACNT films do not help to improve properties of copper matrix. Instead, composites fabricated by high cooper low acid pl ating solution have features of lower surface roughness. The features of SACNT film were maintained during electroplating and the bonding at the interface is well. Tensile and yield strength of composites are improved significantly while high conductivities are not obviously influenced.Composites made by high cooper low acid plating solution have best overall performances with 2.6% volume fraction of SACNT films. The tensile strength reached 272MPa(40.7% higher than matrix) and the electrical conductivity reached 84.7%IACS(3.4% lower than matrix). Theoretical calculations of strengths and conductivities of composites in dicated tremendous potential in improve of strengths if the bonding at the interface between CNT and copper could be further improved. At the same time, conductivity of copper matrix could be maintained because of the high conductivity of carbon nanotube.