Deposition and characterization of diamond-like nanocomposite coatings grown by plasma enhanced chemical vapour deposition over different substrate materials

Abstract

Diamond-like nanocomposite (DLN) coatings have been deposited over different substrates used for biomedical applications by plasma-enhanced chemical vapour deposition (PECVD). DLN has an interconnecting network of amorphous hydrogenated carbon and éuartz-like oxygenated silicon. Raman spectroscopy, Fourier transform-infra red (FT-IR) spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) have been used for structural characterization. Typical DLN growth rate is about 1 μm/h, measured by stylus profilometer. Due to the presence of éuartz-like Si:O in the structure, it is found to have very good adhesive property with all the substrates. The adhesion strength found to be as high as 0.6 N.on SS 316 L.steel substrates by scratch testing method. The Young's modulus and hardness have found to be 132 GPa and 14.4 GPa, respectively. DLN coatings have wear factor in the order of 1×10-7 mm3/N-m. This coating has found to be compatible with all important biomedical substrate materials and has successfully been deposited over Co-Cr alloy based knee implant of complex shape.