A study of the electrochemical and tribological properties of TiN/CrN nano-layer coating deposited on carburized-H13 hot-work steel by Arc-PVD technique

The purpose of this study is to investigate the tribological and corrosion behavior of TiN/CrN nanostructured multilayer coating on H13 carburized hot-work tool steel. Pack cementation and cathodic arc physical vapor deposition (Arc-PVD) techniques were employed to apply adiffused layer and ahard coating, respectively. FE-SEM and XRD were used for coating characterization. Apin-on-disc wear test and Rockwell Cindenter were employed to study wear behavior and adhesion of the coating. To evaluate the corrosion behavior of the specimens, the specimens were tested by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) after immersion in 3.5% sodium chloride solution for 48 hours. The results of potentiodynamic polarization and EIS curves showed that the TiN/CrN nano-layer coating with apre-carburized treatment demonstrated abetter corrosion behavior than H13 and carburized samples. According to the electrochemical test, the current density of the substrate, carburized, and pre-carburized TiN/CrN coated samples were 1.070, 0.875, 0.487 µA/cm2, respectively. This improvement in corrosion resistance is due to the high density of the TiN/CrN nano-layers coating that prevents the diffusion of the corrosion solution into the substrate.