Tribological and Electrochemical Properties of AISI D3 Steel Coated with Hafnium Carbon Nitride

In this research work, hafnium carbonitride (HfCN) coatings were developed via physical vapor deposition with the aim to determine the electrochemical behavior of the HfCN layers on industrial steel substrates. The HfCN coatings, deposited at various negative bias voltage were characterized by X-ray diffraction (XRD), exhibiting the crystallography orientations corresponding to a mix of HfCN, HfC and HfN phases, while the X-ray photoelectron spectroscopy (XPS) measurements were used to determinate the chemical composition of the carbon nitride coatings. By using electrochemical impedance spectroscopy (EIS) and Tafel curves, it was possible to estimate the electrochemical behavior of the HfCN coatings in a sodium chloride (NaCl) solution. Moreover, scanning electron microscopy (SEM) was performed to analyze morphological and chemical surface changes on the HfCN layer due to the reaction in NaCl/HfCN/steel surface interface. The electrochemical behavior of the HfCN coatings in relation to the uncoated AISI D3 steel showed a reduction of 98 % in corrosion rate, indicating that the applied HfCN coatings may be a promising material for industrial applications.