Parametric Optimization of Electroless Ni-P coatings using Taguchi method

Abstract

The present work deals with surface roughness characteristics of electroless Ni-P coatings. The optimised process parameters have been determined based on L27 Taguchi Orthogonal array. Bath concentration of nickel sulphate, concentration of sodium hypophosphite and temperature of bath has been considered as variable in this study. The optimum combinations of process parameters and surface roughness have been considered as response variable of the study. It has been found that 24 g/L of Nickel Sulfate, 25 g/L of Sodium Hypophosphite and 80°C temperature gives the minimum surface roughness of the Ni-P coated sample which was 0.23μm. Characterisation of the substrate and the as deposited samples were done by scanning electron microscope (SEM) and optical microscopy for surface morphology, energy-dispersive X- ray analysis (EDAX) for element analysis and X-ray diffraction for phase analysis.