Influence of Jet Rate on the Structures and Corrosion Resistances of Jet Pulse Electrodeposited Ni-SiC Nanocoatings

In this report, Ni-SiC nanocoatings (Ni-SiC NCs) were successfully fabricated on the Q235 steel matrix while employing the approach of jet pulse electrodeposition (JPED). The impact of jet rate on the resistance to abrasion and corrosion, plating mechanism, thickness, and microstructure of Ni-SiC NCs was studied. In addition, a COMOL software was employed to simulate the JPED processing area under different jet rates. The findings revealed that Ni-SiCs fabricated at a 2.5 m/s jet rate resulted in the formation of nickel grains with the smallest mean size of 42.1 nm. Moreover, the mean size of SiC nanoparticles in the Ni-SiC nanocoating was 24.3 nm. Three jet rate (Jr) values of 1.5 m/s, 2.5 m/s, and 3.5 m/s were used to acquire the Ni-SiC NCs with various thicknesses of 39.4 μm, 78.6 μm, and 61.1 μm, respectively. Smooth and compact surface morphologies were seen in the Ni-SiC NCs formed at a jet speed value of 2.5 m/s. Compared to other composites, Ni-SiC NCs produced at a jet rate value of 2.5 m/s showed bigger and thinner diffraction peaks of nickel grain. XRD findings revealed that the phases (SiC phase and Ni phase) were present in three composites. In addition, advantageous properties such as a pinning effect and a clean microstructure were also imparted to the prepared Ni-SiC composite samples by the addition of SiC nanoparticles. The Ni-SiC nanocoating deposited at 2.5 m/s possessed a maximum hardness of 896.3 Hv, signifying a 26.4% increase over the coating produced at 1.5 m/s. Moreover, the mean corrosion current density found for the Ni-SiC NCs formed at Jr = 2.5 m/s was the lowest (6.2 × 10^-5 A/cm²), indicating the corrosion resistance at the highest. However, the Ni-SiC NCs deposited at Jr = 1.5 m/s had the largest corrosion resistance (1.6 × 10^-4 A/cm²) among all three nanocoatings, which was significantly greater (a 61.3% increase) than that of the coating formed at 2.5 m/s. This research provides a technical support for the simulation and testing of nickel-based coatings.