The microstructure and tribological properties of copper surfaces implanted with carbon ions

Carbon ions were implanted into copper surfaces to a dose of 1×1018 ions cm−2 at 50 keV, and the as-implanted specimens were studied by Raman spectroscopy, selected area diffraction (SAD), transmission electronic microscopy (TEM) and high-resolution electronic microscopy (HREM). The Raman spectra indicate that diamond-like carbon (DLC) was formed on/in the copper surfaces. From HREM images, it is observed that the copper forms amorphous or nano grains and contains a large number of amorphous carbon and nanometre graphite clusters (<5 nm). Considering the formation of these microstructures in the C implanted specimens, it is understandable that the friction coefficient showed a reduction.