Investigation and optimization of machining parameters in drilling of carbon fiber reinforced polymer (CFRP) composites

Abstract

Purpose This paper aims to attempt to use grey relational analysis (GRA) coupled with Taguchi technique for the optimization of machining parameters (cutting speed, feed rate and drill bit type) with multiple performance characteristics of delamination factor, surface roughness and circularity in drilling of carbon fiber-reinforced polymer (CFRP) along the fiber direction. Design/methodology/approach Machining trials involved drilling of 6-mm diameter holes on 8-mm-thick CFRP plates was performed according to L27 (313) Taguchi’s orthogonal array technique using the drill material of high speed steel (HSS), Titanium Nitride (TiN) and Titanium Aluminium Nitride (TiAlN). Analysis of variance has been used find the effect, percentage contribution and significance of the process parameters, namely, cutting speed, feed rate and drill bit type. Findings The Taguchi technique is combined with the GRA to find the optimum process parameter which minimizes the delamination factor, surface roughness and circularity within the range of parameters investigated. The effective implementation of the hybrid approach helps to produce quality and defect free holes. Originality/value Experimental investigation on delamination factor, surface roughness and circularity in drilling of CFRP along the fiber direction using Taguchi-GRA was seldom reported.