Electrodeposited FeNiWMoMn high-entropy alloys: synthesis, characterization, and annealed

Abstract

The electrodeposition method was used for FeNiWMoMn – High-entropy alloy (HEA) coating on a Copper substrate in an aqueous medium. The temperature was set at 75 °C and the deposition time was varied as 30 min, 60 min, and 90 min with a constant current density of 1A/dm². The 60-min deposited films were exposed to one hour of annealing at 200 °C to study the effects on their magnetic and structural properties. FeNiWMoMn alloy coatings were characterized using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray spectroscopy (EDS) and Electrochemical Impedance Spectroscopy (EIS). From the X-ray diffraction analysis, it was observed that they exhibit a cubic crystal structure. The crystalline size measured 27 nm, 26 nm, and 25 nm for deposition times of 30, 60, and 90 min, respectively. Annealed indicates increased crystallite size and reduced dislocation density, contributing to improved mechanical properties. The EDS results confirm that the sample has all of the required elements. The atomic weight percentage of Ni and Fe increases as the deposition period increases, whereas W and Mn decrease. The corrosion rate of coated FeNiWMoMn high-entropy alloy increases as the deposition time increases. The polarization resistance values start to decrease. After Annealing corrosion rate decreased and polarization resistance increased. The surface roughness properties of synthesized alloy are also investigated using AFM and found that the surface roughness of FeNiWMoMn alloy reduces as deposition time increases. Annealing improves the properties of Ni–Fe–W–Mo–Mn thin films for advanced applications.