Applying Ni-P-PTFE composite coatings by electrodeposition method and investigating their corrosion and wear resistance

The results of various research activities show that coating is one of the effective ways to increase the corrosion resistance and wear of metallic substrates. Synthesizing composite coatings using nanoparticles can also further protect the substrate. In this study, using electroplating process and PTFE particles (with concentrations of 10, 20 or 30 g / l), Ni-P-PTFE coatings were prepared and their corrosion and abrasion properties were investigated and compared with Ni-P coating. Using scanning electron microscopy (SEM ) and X-ray diffraction (EDS) methods, the surface morphology and elemental composition of the coatings were studied and finally, using open circuit potential (OCP) techniques, electrochemical impedance spectroscopy (EIS) and polarization techniques, the corrosion resistance of the resulting coatings were evaluated in NaCl solution. M icrohardness and pin on disk tests were also utilized to investigate the effect of PTFE concentration on the tribological properties of the coatings. The results of SEM and EDS studies confirmed the formation of nanocomposites. Electrochemical studies also showed that Ni-P-PTFE coatings, at a concentration of 20 g/L PTFE, had the highest electrochemical corrosion resistance. M icrohardness decreased with increasing PTFE particles in the coating and reached its lowest value in 20 g/l PTFE . Using the wear test, the lowest coefficient of friction obtained in composite coatings obtained at a concentration of 20 g/l, which shows the applicability of PTFE particles as a solid lubricant in Ni-P coatings.