Influence of Nitrogen Flow Rate on the Microstructure and Properties of N and Me (Me=Cr, Zr) Co-doped Diamond-like Carbon Films

In this paper, Me (Me=Cr, Zr) and N co-doped diamond like carbon (DLC-MeN) composite films were prepared on cemented carbide substrates by pulsed bias arc ion plating. The effect of nitrogen flow rates on the microstructure and properties of the films were investigated by X-ray photoelectron spectroscopy (XPS), Raman spectra, grazing incident X-ray diffraction (GIXRD), high resolution transmission electron microscopy (HRTEM) and nano-indentation. Raman, GIXRD and HRTEM results show that the deposited films are nanocomposite films with MeN nanocrystalline phase embedded within DLC amorphous matrix, which are vital for the mechanical properties of the films. The nitrogen flow rate has significant effect on the compositions and structures and hence on the hardness and elastic modulus of the films, and increasing nitrogen flow rate decreases drastically the hardness and elastic modulus of the films.