Multi-objective Optimization in Drilling of GFRP Composites: A Degree of Similarity Approach

AbstractComposite materials have been gaining immense importance in manufacturing industries, particularly in aerospace and automotive industries, due to their excellent properties as compared to other conventional metals. In manufacturing sector, drilling is a very common machining operation; whilst drilling of glass fiber reinforced polymer (GFRP) composite is substantially different from metallic materials due to delamination, fiber pull-out etc. In order to produce satisfactory product quality (GFRP drilled hole), investigations on machining and machinability aspects of GFRP composites are indeed essential. Understanding of the effect of process variables viz. drill speed, feed rate, drill diameter, plate thickness etc. is very important in order to select optimal machining condition towards improving overall machining performance. Therefore, this work focuses on the analysis of drill force (thrust), torque, surface roughness (Ra) and delamination behavior (of the drilled hole) as a function of drilling process parameters. The unified aim of this work is to determine an optimal machining environment based on the concept of the ‘Degree of Similarity Measure’ between each alternative and the ideal solution using alternative gradient and magnitude; TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) and Deng's solution