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 58.36 Ni 36.01 Co 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 53.84 Ni 41.66 Co 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.