Wear behaviour of electroless Ni–P coatings and optimization of process parameters using Taguchi method

This paper reports an experimental study of wear characteristics of electroless Ni–P coatings sliding against steel. Coating process parameters are optimized for minimum wear based on L27 Taguchi orthogonal design with four process parameters, viz., bath temperature, concentration of nickel source solution, concentration of reducing agent and annealing temperature. It is observed that annealing temperature and bath temperature have the most significant influence on wear characteristics of electroless Ni–P coating. The interaction of bath temperature and concentration of nickel source solution has some significant influence on wear. The surface morphology and composition of coatings are also studied with the help of scanning electron microscopy, energy dispersed X-ray analysis and X-ray diffraction analysis. The wear mechanism in EN coatings is found to be abrasive wear.