Nanocomposite Ni-TiN coatings were prepared by ultrasonic electrodeposition and the effects of ultrasonication on the coatings were studied. X-ray diffraction analysis was utilized to detect the crystalline and amorphous characteristics of the composite coatings. The surface morphology and metallurgical structure were observed by scanning electron microscopy, high-resolution transmission electron microscopy and scanning probe microscopy. The results showed that ultrasonication had great effects on TiN nanoparticles in composite TiN particles in the coatings. Moreover. the TiN nanocoatings. The moderate ultrasonication conduced to homogeneous dispersion of TiN particles that entered and homogeneously dispersed in the composite coating led to an Increase in the number of nuclei for nucleation of nickel grains and inhibition of grain growth. Therefore, the introduction of ultrasonication and TiN nanoparticles resulted In the formation of smaller nickel grains. The average grain diameter of TiN particles was similar to 33 nm, while Ni grains measured approximately 53 nm. (C) 2007 Elsevier B.V. All rights reserved.