Study of the Effect of Current Density on the Metallurgical Properties of AlFeCrNiTi High Entropy Alloy Coating Produced by Pulse Plating

Abstract

Pulsed current electrodeposition was used to deposit a novel AlFeCrNiTi high entropy alloy coating on copper. As a first step, cyclic voltammetry was used to determine the minimum current required to reduce all metal ions on the substrate. Afterward, 150, 250 and 350 mA/cm² current densities were investigated for their effects on coating microstructure, corrosion, mechanical, and magnetic properties. SEM, EDS, and XRD studies were conducted to examine the coatings morphology, chemical composition, and phase analysis. A microhardness, wear, VSM, DC polarization, and EIS techniques were used to study the mechanical, magnetic, and corrosion properties of the coatings. As a result of EDS, XRD, and thermodynamic calculations, AlFeCrNiTi high entropy alloy coating with the BCC + FCC combined structure has been confirmed. Moreover, it was determined from other tests that coatings with a uniform structure, maximum microhardness (520 HV) and charge transfer resistance (4306 Ω.cm²), the lowest corrosion current density (0.088 µA/cm²), and favorable wear properties were obtained at a pulsed electroplating current density of 250 mA/cm². Due to the higher nickel and iron content of the coating created at 150 mA/cm², maximum saturation magnetization was achieved (105.64 emu/g).