Improved characteristics of Ni-electrodeposited coatings via the incorporation of Si and TiO2 particulate reinforcements

In this work, micron-sized Si and nano-sized TiO2 particles were added to Ni-matrix electrodeposited coatings, where the amount of the TiO2 particles in the plating bath was the independent variable of the study. The influence of the reinforcement addition on the structure, micro-hardness, and corrosion behavior of the coatings was investigated. The results indicated that due to the addition of the Si particle and the optimum value of the TiO2 particle to the plating bath, remarkable improvements in the coating's characteristics are achieved. It was found that the incorporation of the reinforcements changes the crystallographic texture of the Ni-matrix. Also, the nickel-matrix crystalline size of the coatings considerably decreases, the micro-hardness increases, the corrosion current density is reduced, and the corrosion potential is shifted toward the noble direction. In conclusion, the development of this type of composite coatings can enlarge the application of nickel-based electrodeposited coatings in the industry.