Corrosion resistance of low-carbon steel modified by plasma nitriding and diamond-like carbon

In this paper, the corrosion resistance of nitrided and diamond-like carbon (DLC)-coated SAE 1020 steel samples was investigated. The DLC coating was deposited after plasma-nitriding. The structure and composition of different phases of the samples were characterized by Vickers micro-hardness, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. The corrosion behavior of the samples was investigated by electrochemical methods using a 0.1 mol L-1 H2SO4 solution. The results obtained from sample characterization agreed well with those obtained from electrochemical corrosion methods. The 500-W DLC coating exhibited the best corrosion -resistance. The DLC-coated samples showed better corrosion-resistance than uncoated samples.