34 International Journal of Surface Engineering and Interdisciplinary Materials Science, 2(2), 34-52, July-December 2014 Copyright © 2014, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. ABSTRACT Electroless Ni-P coatings with hard Al2O3 composite particles are developed on mild steel specimens. The coating parameters viz. source of nickel ions, concentration of reducing agent and concentration of Al2O3 particles are used as coating parameters to minimize wear rate (wear depth in µm) and friction coeffcient. As annealing temperature strongly affects hardness and wear resistance of coating, it is considered as fourth parameter. In the present study wear depth and friction coeffcient are used as response variables. To convert multiple responses into single performance index, Weighted Principal Component Analysis (WPCA) is used. Taguchi L27 OA with four process parameters at three levels is used to conduct the experiments. ANOVA is used to fnd out the signifcance of each coating parameters and their interactions. Annealing temperature is found to be the most signifcant factor followed by concentration of composite particles. The surface morphol- ogy, composition and phase structure analysis are done with the help of SEM, EDAX and XRD respectively. Optimization of Friction and Wear Properties of Electroless Ni-P-Al2O3 Composite Coatings Prasanta Sahoo, Department of Mechanical Engineering, Jadavpur University, Kolkata, India Prasanna Gadhari, Jadavpur University, Kolkata, India Keywords: Electroless Coating, Friction, Ni–P–Al2O3, Optimization, Wear, Weighted Principal Component Analysis (WPCA) INTRODUCTION In industries machine components, tools and other equipments are mostly related to sliding and rolling type of motion in between them. In such situations the components or tools may be failed due to lower hardness and wear resistance. Hence it is essential to improve the hardness, wear resistance and frictional resistance of said components to increase their life. In present days coating plays vital role in surface engineering techniques, as these are well suitable for ex- cellent wear resistance, frictional resistance, erosion, corrosion resistance and higher hard- ness instead of protecting the base metal from environmental changes. Electroless coating or autocatalytic coating is defined as the deposition of a metallic coating by a controlled chemical reduction that is catalyzed by the metal or alloy being deposited. Unlike electroplating, it is not necessary to pass an electric current through the solution to form a deposit. The main advantages of these coatings are, these are having uniform and smooth thickness irrespective of complicate DOI: 10.4018/IJSEIMS.2014070103