The Effect of Pulse Plating Parameters on The Microstructure and Properties of Cu-TiO2 Nanocomposite Coating

In this study, Cu-TiO2 nanocomposite coatings were electrodeposited from a copper sulfate bath containing dispersed TiO2 particles of 20 nm mean size. These coatings were prepared under pulse current condition on steel substrate in room temperature. The influence of pulse frequency and average current density on the microstructure and incorporation of TiO2 nanoparticles in coating were investigated by scanning electron microscopy (SEM) and (EDS) analysis. The crystallite size of the coatings calculated from the x-ray diffraction patterns using the Scherrer equation. Micro hardness of the coatings was assessed using a Vickers micro-indenter. Performance of the coatings was investigated by the potentiostatic polarization method. Process parameters were optimized with respect to TiO2 content of the composite coating and micro hardness. The optimized pulse frequency and average current density were 20 Hz and 2 A/dm2 respectively. The amount of TiO2 particles incorporated into the coating that were produced under the optimum plating conditions was 1.9 wt. %; also, the crystallite size of this coating was 27 nm, the micro-hardness was 180 Hv and the corrosion rate was 0.56 mpy.