Investigation of surface roughness and MRR for turning of UD-GFRP using PCA and Taguchi method

This paper investigates the machinability of unidirectional glass fiber reinforced plastics (UD-GFRP) composite in turning process. Taguchi L18 orthogonal array is used for experimental design. The six parameters i.e. tool nose radius, tool rake angle, feed rate, cutting speed, cutting environment (dry, wet and cooled) and depth of cut are varied to investigate their effect on output responses. An attempt has been made to model the two response variables i.e. surface roughness and material removal rate using Principal Component Analysis. PCA is a technique of great practical importance in many applications of statistical inference, when it becomes difficult to relate a large number of independent variables with a number of dependent outcomes without having enough observations to carry out the analysis in a reliable way. Correlated responses are transformed into uncorrelated or independent quality indices called principal components. From the experimental results, it is evident that the surface roughness increases as feed rate increases. It is found that feed rate is more significant factor followed by depth of cut and cutting speed. Feed rate = 0.2, depth of cut = 1.4 mm and speed = 159.66 m/min produces the optimum value of surface roughness μRa = 1.498 μm and the optimum material removal rate MRR = 330.267 mm3/s.