Effects of the Post-deposition Annealing Treatment on the Electrochemical Behavior of TiN Coating Deposited by CAE-PVD Method

The main purpose of this investigation is to assess the effect of post-deposition annealing treatment on the electrochemical behavior of TiN coating developed on AISI 304 stainless steel substrate using cathodic arc evaporation physical vapor deposition (CAE-PVD). Post-annealing treatment at 400 ºC was performed on the coated substrate for 1 h. The studied samples were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) tests. The preferred orientation of TiN (111) was identified by XRD patterns and the crystallinity of the coating increased after annealing treatment. SEM observations indicated that TiN coatings free of cracks were successfully developed on the substrate. The electrochemical measurements elucidated that the annealed coating had better corrosion resistance compared to that of the as-deposited coating with a lower current corrosion density. This investigation implied that improved corrosion performance of the TiN coating can achieved by performing post-deposition annealing treatment.