Synthesis of Ultrafine Dispersed Coating by Electrodeposition

Abstract

Ni-TiO2 and Ni-ZrO2 metal matrix composite coatings were prepared by using watt’s solution through electrodeposition process. Different weight percentage of Titania and Zirconia powder along with different concentration of surfactant were used for the present study. For the determination of optimum condition of deposition, time of deposition, solution pH, particle amount and surfactant amount were taken as variables, whereas current density and temperature of the bath were maintained constant. To resist agglomeration of ultra fine particles in plating bath due to high surface free energy and to get homogeneous coating, stirring and ultrasonic agitations have been used.
The availability and compositions of coatings were studied by X-ray diffraction spectrum and energy dispersive spectroscopy (EDS). The wear behavior of the pure Ni, Ni-TiO2 and Ni- ZrO2 composite coatings were studied by a ball-on-plate wear tester. The microhardness and wear resistance of the coatings increase with increasing of weight percentage of particles content in the coating. The hardness of the resultant coatings was also measured and found to be 375 VHN for Ni coating, 647HV for TiO2 and 401HV for ZrO2 depending on the particle volume in the Ni matrix. The results showed that the wear resistance of the composite coatings increased as compared to unreinforced Ni deposited material.