The Mechanical and Tribological Properties of Copper Matrix Composites Reinforced with Carbon Nanotubes Prepared Via a Powder Metallurgy Method

摘要

Copper matrix composite reinforced with carbon nanotubes (CNTs) was fabricated by hot isostatic pressing (HIP) and subsequently hot extrusion (HE). The morphology and phase of the powders, the distribution of CNTs in matrix and fracture surface morphologies was observed by scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). The mechanical and tribological properties of the composites were also tested. It was found that the HIP and HE process can significantly improve the relative density of the Cu-CNTs composites with the same volume fraction of CNTs. An increased CNTs contents (3, 5, 10 vol.%) will result in a slightly decreased tensile strength and elongation. Such tendencies are correlated with the content and distribution of CNTs. Moreover, the friction coefficients and wear rates reduce significantly by the addition of CNTs. The abrasive and delamination wear are the dominant wear mechanisms of the composites. It is believed that the superior mechanical and tribological performances of Cu-CNTs composites are attributed to the unique strengthening effect as well as the higher lubricating efficiency of carbon nanotubes, which demonstrates that CNTs is an ideal filler for copper matrix composites, acting as not only an impactful lubricant but also a favorable reinforcement.