JME_V5_N4_RP4 Ajay Malik Hari Singh Satya Prakash Journal on Mechanical Engineering 2249 - 0744 5 4 27 34 Flame Spray, Taguchi, Grey Relational Analysis, Coating Flame spraying has emerged as the most promising technique among all thermal spraying techniques for depositing a higher quality abradable coating. The present work deals with a statistical design of experimental study of flame spraying Metco 301NS powder. The choice of the optimum coating parameters plays an important role in the quality of the coating, the coating cost and increasing the lifetime of the coated parts. Coating experiments were performed with a Taguchi (L8) design to optimize the flame spray process parameters. In this study, the influence of the different coating variables like oxygen, acetylene, rpm, coating angle and spray distance on various performance features such as hardness, roughness, porosity and thickness were evaluated. The attributes of the coating were correlated with the change in the parameters and their relative importance, contribution ratios and total variance were calculated using the Taguchi method. Since the thermal spray coating is a multiple feature technique, a multi objective optimization technique, Grey Relational Analysis (GRA), was used to optimize the process parameters. The investigation revealed the optimal combination of process parameters for oxygen (40 L/min), dissolved acetylene (50 L/min), rpm (4), spray angle (60 degree) and spray distance (7 inch). The results were verified through confirmation tests. August - October 2015 Copyright © 2015 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=3618