Effect of NiP-SiC nanocomposite interlayer on corrosion behavior of diamond-like carbon/Steel

Diamond-like carbon (DLC) films are among attractive options to increase wear and corrosion resistance. However, nano-cracks in the DLC films as well as insufficient adhesion to the steel substrates limit their use as a protective layer. In this work, the electroless Nickel-phosphorus (NiP) and NiP-SiC nanocomposite interlayers were used as a bond coat between steel substrate and DLC film, which can also act as corrosion-resistant barrier layer. The DLC film was deposited by the radio frequency plasma enhanced chemical vapor deposition method using acetylene as a precursor. The carbon atomic bonds of the coating have been analyzed by Raman spectroscopy. The corrosion behavior of the samples was investigated by potentiodynamic and electrochemical impedance spectroscopy methods and the surface of the specimens was examined by field emission scanning electron microscopy after the corrosion tests. The results show that applying NiP and NiP-SiC nanocomposite interlayer increased the corrosion resistance of the bilayer specimens.