Protective carbon layer for chemical corrosion of stainless steel

摘要

Hydrogenated carbon (a-C:H) films were studied as an alternative material to be used as protective layer on steel, because of their chemical inertness, wear resistance, thermal stability, thermal conductivity. The films were deposited on stainless steel, plain steel and silicon wafers by a RF magnetron sputtering system at 0.6 Pa and RF power of 150 W, at room temperature. A methane plasma was used in these processes. Wet etching tests were carried out using acids (H_2SO_4, HNO_3, HCl, HF), alkaline solutions (NH_4OH, KOH), organic solvents (2-propanol, xylene and acetone). The samples were analysed by Fourier transformed infrared, Raman spectroscopy, atomic force microscopy and cyclic voltammetry. The low degradation and corrosion levels of the samples show the high chemical resistance of the a-C:H films indicating that they are a promising material to be used as protective layer in many applications of the chemical industry.