the morphological, corrosion and mechanical properties of ni/cr oxide-ni-al nano-composite coating on st12 by epd

Metal oxides have a wide industrial application, and are an important component of engineering nanocomposites that can improve the surface properties of metals. in the present study, the ni-cr oxide nanocomposite was synthesized by co-precipitation and then coated on the surface of carbon steel st12 using electrophoretic deposition (epd) at 110 v for coating time of 3 min. the properties of the synthesized nanocomposite and coatings were investigated by xrd, ftir, tem, fesem and optical microscope (om). the results showed nio and the cubic spinel nicr2o4 with a crystallite size of 28.8 nm and a particle size of 60-80 nm in the calcined powder of the co-precipitated material. wear and corrosion behavior of the st12 substrate and the coatings was investigated using ball-on-disk wear, eis and polarization tests. the xrd analysis of the coating materials after sintering revealed ni, nial2o4 and nicr2o4. the results showed that the ni/cr oxide-ni-al nanocomposite was successfully coated on the st12 surface by epd and significantly improved the wear and corrosion resistance. the average coating thickness was 10.76 µm. the mass of worn material was measured to be 1.6 and 1.9 mg after 120 m traveling for the coating and the substrate, respectively. according to the tafel analysis, the corrosion rate was 10.3 and 140.3 µ a·cm−2, respectively. using the eis data, the corrosion mechanism was evaluated and the corresponding equilibrium electrical circuit (eecs) was simulated. the corrosion resistance (total r) was found to be 7934.6 and 134.49 ω.cm for the coated sample and the bare st12 substrate, respectively.