Heat Treatment of Pulsed Electroplated Nickel Deposited on AA2024 Aluminum

In this study, pure nickel was deposited on AA2024 aluminum via pulsed electrodeposition using two duty cycles (25 % and 50 %) at two different frequencies (50 and 100 Hz). The coated specimens were then heat-treated in an argon atmosphere at 500 °C for one hour. The treated specimens were characterized using Optical Microscope (OM), Scanning Electron Microscope (SEM) equipped with energy dispersive spectrometer (EDS), and X-Ray Diffraction (XRD) analysis. According to the results, the coatings were thickened upon increasing the duty cycle and frequency. Heat treatment of the nickel-coated specimen under the duty cycle of 25 % and frequency of 50 Hz experienced formation of Al3Ni intermetallic compound at the interface of the nickel coating and aluminum-based substrate. Heat treatment adversely affected the corrosion resistance of the nickel-coated specimens. Nevertheless, the specimens with Al3Ni intermetallic compound at their interface demonstrated better corrosion resistance among heat-treated materials.