Surveying of the corrosion inhibition property of 316L stainless steel coated with polymer-based nanofibers obtained by electrospinning method in artificial body liquid environment

In this study, the surface of 316L stainless steel (SS) was coated with ten different contents of polycaprolactone (PCL) nanofibers, which were obtained by electrospinning from a PCL solution containing various corrosion inhibitors (zinc acetate, nickel acetate, copper acetate, 2 phenyl thiosemicarbazide (2F TSC), 4 phenyl thiosemicarbazide(4F TSC) and graphite. The PCL-based nanofibers were doped with ZnO, CuO, NiO, 2F TSC, 4F TSC, and graphite in the following compositions: PCL+Graphite+CuO+NiO+ZnO, PCL+ZnO+Graphite, PCL+ZnO +NiO+CuO, PCL+ZnO, PCL+Graphite, PCL+ZnO+2F TSC, PCL+ZnO+NiO+CuO+4F TSC, PCL+ZnO+NiO+CuO+2F TSC, bare PCL, and PCL+ZnO+4F TSC. After coating with these different types of nanofibers, measurements were taken with electrochemical techniques such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) in phosphate buffer solution (PBS) for 1 hour to investigate corrosion inhibition properties. Corrosion inhibition of 316L SS coated with three of the best performing nanofiber types (PCL, PCL+ZnO, PCL+(ZnO, NiO, CuO)) in artificial body fluid (SBF) in a time period of 0-192 hours was also detailed. Corrosion resistance of 316L stainless steel was tested using a potentiostat device. The evaluation of the anti-corrosion efficiency of the nanofiber layer was measured by electrochemical techniques like PDP and EIS. The surface morphologies and chemical composition of the surface films were determined using scanning electron microscopy with energy-dispersive X-rays (SEM-EDX). The hydrophilic nature of sample surfaces was also determined by contact angle analysis. Furthermore, many parameters such as breakpoint frequency, coating damage index and coating delamination index extracted from Nyquist, Bode graphs were discussed. The results show that the water contact angles of the chosen three nanofiber samples were found to be 117o, 80o, 100o for PCL+(NiO,CuO,ZnO), PCL+(ZnO), PCL, respectively. The protection efficiency was follow an order PCL/(NiO-CuO-ZnO) 90,8% ˃ PCL/(ZnO) 89,67% ˃ PCL 85,01% in SBF solution after 192 hours.