Improvement of hardness and corrosion resistance of SS-420 by Cr+TiN coatings

Purpose: Double layer Cr+TiN thin films were coated on SS-420 substratum to achieve a corrosion resistive system. Design/methodology/approach: Ion coating technique was employed for deposition of TiN on stainless steel and subsequently, chromium was coated resulting Cr+TiN composite. Findings: : In this work we have purposed to improve the natural defect of hard coating material, TiN against corrosion phenomena. This task was fulfilled by formation of a double layer Cr+TiN, which was characterized by glow discharge optical emission spectroscopy (GDOS) for compositional analysis of content elements. X-ray diffraction (XRD) technique was utilized to investigate films crystalline structure. It was revealed that the composite with (111) plane of reflection possess very good corrosion resistive behavior. Scanning electron microscopy (SEM) image showed a double layer configuration. Research limitations/implications: As the study was carried out on limited surfaces, it is necessary to endeavour further work on larger area. Practical implications: As the galvanic corrosion is a common problem in thin film technology due to its pinholes and small grains, therefore, any attempt to overcome this problem is encouraged. Originality/value: : Due to limited work and data available on literature about the corrosion resistive thin layers, it may regard this work as a valuable and remarkable approach.