Studying the in vitro corrosion response of nanostructured TaN coatings in Hank's physiological solution

The goal of this research is to determine the effect of N₂ pressure to argon pressure on the microstructural analysis and corrosion behavior of nanostructured TaN deposited coatings using a reactive DC-magnetron sputtering (RDCMS) technique. The samples coated microstructure was studied by the X-ray diffraction (XRD) and scanning electron microscope (SEM), and elemental distribution was studied using energy-dispersive X-ray spectroscopy (EDS). To investigate the corrosion behavior of nanostructured TaN coatings, the potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) tests were performed in Hank's physiological solution. The results of different tests revealed that the coating with a content of 17.6% P_N2/P_Ar consisted of hexagonal and orthorhombic TaN phases and had denser microstructure and free pores. This coating showed superior corrosion behavior in comparison to the other ones. Also, the corrosion resistance of this coating raised by increasing the time of immersion from 48 to 168 h.