Ultrasound-Assisted Electrodeposition of Fe-Ni-Co Ternary Alloy Film: Microstructure, Corrosion Resistance, and Soft Magnetic Property

Fe-Ni-Co alloy films demonstrate outstanding soft magnetic properties and are widely used as magnetic materials. The ultrasonic-assisted electrodeposition method is highly regarded for its merits in improving alloy film performance. In this study, Fe-Ni-Co alloy film with a uniform composition was fabricated through ultrasonic-assisted electrodeposition. The effects of the electrodeposition parameters on the composition and microstructure of the Fe-Ni-Co alloy films were studied. The results revealed that lower initial electrolyte pH, temperature (T), and ultrasonic power (P) were conducive to the increase of the iron content of the alloy films. As the ultrasonic power increased, the crystal structure of the Fe-Co-Ni films changed from bcc (FeCo) to fcc (NiFe), and the mean grain size decreased. When the electrodeposited condition was pH = 2, T = 50°C, and P = 45 W, the Fe_58.36Ni_36.01Co_5.63 alloy film showed a better corrosion resistance than 304 stainless steels. When the electrodeposited condition was pH = 2, T = 50°C, and P = 90 W, the Fe_53.84Ni_41.66Co_4.48 alloy film exhibited good magnetic properties, and the saturation magnetic induction and coercivity were 1.75 T and 85 A/m, respectively, which was much better than Fe-Co-Ni alloy films (Ni: about 40 wt.%) prepared by traditional electrodeposition.