IEEE-Intenational Conference On Advances In Engineering, Science And Management (ICAESM -2012) March 30, 31, 2012 12 Multiple Performance Optimization in Drilling of GFRP Composites Using Grey Analysis S. Ranganathan\ T. Senthilvelan b , S. GopalakannanC a Department ofMechanical Engineering, Saveetha School of Engineering, Saveetha Universiy, Saveetha Nagar, Chennai-602I05, India e -mail: srn 95@rediffmail.com • b, C Department ofMechanical Engineering, Pondichery Engineering college, Pondicherry - 605104, India .e-mail: tsenthilvelan@hotmail.com. gopalakannans@yahoo.com Abstact- Glass ibre-reinforced polymer (GFRP) composites are alternative to engineering materials because of economic, light weight, corrosive resistance and superior properties. The experimental research under taken by the scholars is a study of impact of multiple performance optimizations in drilling of GFRP using grey analysis. The inluence of drilling parameters on surface quality of GFRP plastic composite material, delamination, thrust force and torque was investigated experimentally. Drilling tests were carried out using we drills of 12 mm in diameter at 600, 900, 1200 and 1500 rpm spindle speeds and at 0.04, 0.08, 0.12 and 0.16 mm/rev feed rates. The signiicant process parameters have been determined by using ANOVA. Optimum level of drilling parameter have identiied by using the values of grey relational grade derived from grey analysis. The analysis of grey relational grade shows that feed rate is the inluential parameter than spindle speed. Keywords- GFRP composites, Drilling, Surface roughness, Delamination, Thrust force, Torque, ANOVA, Grey analysis I. INTRODUCTION Glass ibre-reinforced polymer (GFRP) composites are inds many applications such as aerospace, aircrat, automobile, robots and machine tools because of their excellent properties such as high speciic strength, low thermal expansion, light weight, corrosive resistance and good dimensional stability. For making hole on the GFRP plate, conventional drilling with twist drill remains one of the most economical and eficient machining process for riveting and fastening structural assemblies in the automotive and aerospace industries. Drilling of glass iber-reinforced polymer (GFRP) composite materials are facing diiculties while machining because of ibre pull-out, matrix bonding and ibre uzzing. The ibre debonding leads to subsurface damage, reduced strength and shorter service life. Tsao explained the optimum value of feed rate, spindle speed and diameter ratio for the thrust force and delamination of core-saw drill during carbon iber reinforced plastics [1]. Birhan I�Ik and Ergun Ekici investigated the damage during drilling of woven glass ibre reinforced plastic composites by ANOVA method [2]. Aravindan et al studied the machinablity of GFRP by using the statistical analysis [3]. Arul et al explained the inluence of tool material on dynamic drilling of GFRP composites and optimized the cutting parameter [4]. Prakash et al optimized the delamination factor in drilling medium-density ibreboards using desirability-based approach. They have employed the desirability unction approach to optimize the drilling parameter for minimizing the delamination factor at entry and exit in drilling of MDF boards [5]. Tsao et al presented a novel approach of the equivalent delamination factor to characterize drilling-induced delamination using a core-saw drill. They compared the adjusted delamination factor and the conventional delamination factor. Many researchers reported that the X-ray [6.7], optical microscope [8, 9], ultrasonic C-scan [lO, 11], and digital photograph have been used to acquire the size, shape, and location of delamination on the composite laminates. Singh and Bhatnagar studied the inluence of drilling-induced damage on the residual tensile strength of unidirectional composite laminates and proposed a mathematical model correlating the residual strength with the drilling parameters. Erol kilickap determined the optimum parameters on delamination in drilling of GFRP composites using Taquchi method and predicted that feed rate id the major inluence factor for delamination [12]. Mohan et al reported the delamination analysis in drilling process of glass iber reinforced plastic composite materials [13]. Faras et al investigated on drilling GFRP epoxy composite laminates using specialized and conventional uncoated cemented carbide drills [14]. A number of researchers have applied Grey relational analysis for multi objective optimization of process parameters. For example Patel et al obtained optimal machining parameters by the grey relational grade obtained rom the grey relational analysis for multi-performance characteristic [15]. Ranganathan and Senthilvelan have used grey relational analysis for optimizing the cutting parameters in hot tning [16]. Grey relational analysis based on grey system theory is the solution for solving the problem of complicated interrelationships among the multi-response. For the practical machining of GFRP, it is necessary to determine the optimal machining parameters to achieve less thrust force, less torque, ISBN: 978-81-909042-2-3 ©2012 IEEE