Mechanical, morphological, and corrosion features of Ni–Cr oxide nanocomposite coating deposited on SS304 by EPD

Abstract

AbstractCeramic composites are suitable materials to improve the surface characteristics of steel. Therefore, in this research, Ni–Cr oxide nanocomposite was coated on 304 stainless steel (SS304) by the electrophoretic approach. The effect of chemical composition and coating parameters (time and voltage) was investigated on morphology, corrosion, microhardness, and wear behavior. The nanocomposites were successfully synthesized in three different compositions (Ni–Cr oxides of 70–30, 60–40, and 50–50). The products were coated on the SS304 in 1, 2, and 3 min and 90, 110, and 130 V. Fourier‐transform infrared spectroscopy, X‐ray diffraction, transmission electron microscope, and field emission scanning electron microscopy analyses were employed to investigate the characteristics of the synthesized powder and resulting coatings. The hardness, wear properties, and corrosion resistance of the coating were studied by microhardness, ball‐on‐disk, electrochemical impedance spectroscopy, and polarization methods. The coatings deposited at 1 min and 110 V were sound and free of microcracks. The wear resistance increased by increasing Cr%, so the 50–50 coating showed the best wear resistance with a friction coefficient of .763 and wear mass of 1.6 mg. However, the coating 70–30 presented the highest microhardness of 180.28 Hv. The coating 60–40 had the best corrosion resistance with a corrosion current density of 5.92 µA/cm2. The corrosion resistance improved for thicker coatings.