Measurement and evaluation of delamination factors and thrust force generation during drilling of multiwall carbon nanotube (MWCNT) modified polymer laminates

In recent years, manufacturing industries have demanded high-performance materials for structural components development due to their reduced weight, improved strength, corrosion, and moisture resistance. The outstanding performance of polymer nano-composites substitutes the use of conventional composites materials. This study is concerned with the machining of MWCNT and glass fiber-modified epoxy composites prepared by a cost-effective hand layup procedure. The investigations were carried out to estimate the generation of the thrust force (Th) and delamination factors at entry (DFentry) and exit (DFexit) side during the drilling of fiber composites. The effect of varying constraints on the machining indices was explored for obtaining an adequate quality of hole created in the epoxy nano-composites. The outcome shows that the feed rate (F) is the most critical factor influencing delamination at both entry and exit side, and the second one is the thrust force followed by wt.% of MWCNT. The statistical study shows that optimal combination of S (1650 Level-2), F (165 Level-2), and 2 wt.%70 of MWCNT (Level-2) can be used to minimize DFentry, DFexit, and Th. The drilling-induced damages were studied by means of a high-resolution microscopy test. The results reveal that the supplement of MWCNT substantially increases the machining efficiency of the developed nano-composites.