Ultrasonic-assisted electrodeposition of Ni-Cu/TiN composite coating from sulphate-citrate bath: Structural and electrochemical properties

•Ni-Cu/TiN nanocomposite coating has been fabricated by ultrasonic-assisted electrodeposition.•Effects of TiN nanoparticles and current density on structural and electrochemical properties were investigated.•3D topography, roughness and surface properties were analyzed by various methods.•Corrosion resistance of Ni-Cu/TiN was enhanced by ultrasonic-assisted electrodeposition.•The best corrosion resistance of Ni-Cu/TiN was obtained at 5 A dm−2 under ultrasonic condition. Ni-Cu/TiN nanocomposites were electrodeposited by incorporation of TiN nanoparticles in Ni-Cu matrix from sulphate-citrate bath with additives. Ultrasonic assistance was performed in an external ultrasonic bath at ultrasonic frequency of 40 KHz and acoustic power of 300 W. The effects of current density on surface morphology, structural and electrochemical properties of Ni-Cu/TiN nanocomposites were examined. Results indicated that the presence of TiN changes the texture of nickel coating. Corrosion resistance of the composite deposit was enhanced by ultrasonic-assisted electrodeposition. The average roughness value (Ra) of Ni-Cu/TiN is 26–34 nm, which is rougher than Ni-Cu alloy (Ra = 4–5 nm). Not only the ultrasonic agitation, but also the current density affects the corrosion properties of the products. Ni-Cu/TiN nanocomposite electrodeposited at 5 A dm−2 has the highest corrosion resistance.