Investigating the Microstructure and Mechanical Properties of Cu-5Zn Alloy Nanocomposite Reinforced with Carbon Nanotubes

After the discovery of carbon nanotubes, observations showed that carbon nanotubes have multi-purpose properties and can be used as a reinforcing material for metal nanocomposites. In this research, multi-walled carbon nanotubes have been used as nanocomposite reinforcement with Cu-5Zn alloy base. Carbon nanotubes were added to the nanocomposite in percentages of 0.25-1. Ultrasonic waves were used for good dispersion of carbon nanotubes in the field. Pressing and sintering processes were used to make nanocomposite samples. The microstructure was studied using a scanning electron microscope. The effect of carbon nanotubes on mechanical properties such as microhardness and tensile strength of nanocomposite was investigated. The results showed that the mechanical properties are improved by adding carbon nanotubes. The proposed mechanism for increasing the strength in nanocomposites reinforced with carbon nanotubes is the bridging mechanism. The microhardness of nanocomposites increases linearly with the increase of carbon nanotubes up to 0.75%, and the increase in hardness of nanocomposite with carbon nanotube reinforcing phase is 36% more than copper-zinc base alloy. The tensile strength of copper nanocomposites is 289 MPa by increasing the amount of carbon nanotube reinforcement, which is a significant increase compared to the base copper-zinc alloy with a strength of 165 MPa.