OPTIMIZATION OF PROCESS PARAMETERS FOR MICRO HARDNESS OF ELECTRODEPOSITED TiO2-HAP COATING ON Ti-6Al-4V SUSTRATE USING TAGUCHI METHOD

Abstract

Aim of this work is to fabricate TiO2-HAP composite coatings on Ti-6Al-4V alloy with electrodeposition process and examine the effect of process parameters on micro hardness of TiO2-HAP composite coated Ti-6Al-4V substrate. Voltage, pH of electrolyte and Titania (TiO2) concentration were taken as process parameters. TiO2-HAP composite coatings on Ti-6Al-4V were deposited with help of
electrodeposition process from the standard Watt’s solution. The relationship between process parameters and micro hardness of composite coatings was established by Taguchi method. Design of experiment was carried out by selecting three levels of each parameters and L9 Taguchi orthogonal array design was employed for this purpose. Vickers micro-hardness tester was used to determine micro-hardness of the composite coatings by applying 200 gf for 15 seconds of indentation period. Signal-to-noise ratio and
analysis of variance were employed to determine the significance of the process parameter. The surface morphologies and elemental compositions of coating were analyzed by using scanning electron microscope and energy dispersive spectroscopy.