Optimization of drilling parameters for glass fiber-reinforced nanocomposite materials using Taguchi-based CRITIC-VIKOR method

In this study, custom-fabricated multiwalled carbon nanotube (MWCNT)-reinforced and unreinforced glass fiber-reinforced polymer (GFRP) composites were used. These composites were manufactured via the vacuum-assisted resin transfer molding technique to ensure high-quality, consistent material properties. The study investigates the effects of MWCNT reinforcement ratios, cutting speeds, and feed rates on the drilling performance of GFRP composites. Key processing indicators such as surface roughness (SR), delamination, and thrust force were evaluated. A full factorial design comprising 27 experimental runs was employed. Variance analysis (ANOVA) and the Taguchi method were used for single-response optimization, revealing that the MWCNT reinforcement ratio had the greatest effect on delamination, while feed rate predominantly influenced thrust force. Cutting speed and feed rate were both found to significantly affect SR. For multiobjective optimization, the Criteria Importance Through Intercriteria Correlation-based weighting method was integrated with the Vlse Kriterijumska Optimizacija Kompromisno Resenje (VIKOR) approach. The optimal parameters identified through this methodology were further refined using Taguchi signal-to-noise ratio analysis. According to the VIKOR analysis, feed rate emerged as the most influential factor, with a contribution ratio of 28.48%. The optimal drilling parameters correspond to Experiment No. 10, which involved a 0.5% MWCNT reinforcement ratio, a cutting speed of 25 m/min and a feed rate of 0.10 mm/rev (A2B1C1). Under these conditions, the delamination factor (D-0) was 1.234, thrust force (F) was 82.03 N, and SR (Ra) was 1.575 mu m. This integrated methodology provides a robust framework for optimizing drilling parameters in nanocomposite materials.