This work describes the use of a modified Watt nickel bath to prepare pure Ni and Ni–TiN thin coatingsby the application of ultrasonic electrodeposition (UE) under pulse current (PC) conditions. X-raydiffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM),scanning probe microscopy (SPM) were used to investigate the influences of ultrasonic intensity onphase composition, surface topography, and microscopic structure. The Vickers hardness, wearresistance of Ni and Ni–TiN coatings, and coefficient of friction were also tested. The TEM, SEM, andSPM results showed that under the ultrasonic wave with the intensity of 30 W/cm2, Ni-TiN coatingsexhibited a glossy and uniform surface topography. For NT-2 coating with a superficial area of 4.102μm2, the root means square (Rms) roughness was 36.825 nm and the arithmetic mean roughness (Ra)was 22.658 nm. The average size of Ni grains was 47.1 nm, whereas that of TiN nanoparticles wasobserved as 23.2 nm. The diffraction angle of the coatings with disparate coating parameters in the XRDanalysis was found to be similar to the Ni phase, however, the intensity of diffraction varied. Themicrohardness experiment showed that the minimum microhardness of the Ni film was 387.6 HV.Furthermore, the maximum microhardness value got from the Ni-TiN coating under the ultrasonic wavewith an intensity of 30 W/cm2 was 912.1 HV. Wear and friction evaluation showed that the loss in weightof Ni-TiN coatings performed with 30w/cm2ultrasonic intensity was the smallest, and the averagefriction coefficient was measured to be 0.39, thus exhibiting good resistance to wear.
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