Machinability study, machining performance optimisation and sustainability assessment in laser micro-drilling of CNT/epoxy nanocomposite

Precision drilling of carbon nanotube (CNT)-based polymer matrix composite (PMC) is a demanding operation owing to their promising application. Laser beam machining is possibly a viable alternative to overcome the delamination, burr development, fibre pull-out, and poor surface quality problems associated with traditional drilling processes. The effectiveness of the Nd:YAG laser machining system on CNT/epoxy-based PMC is investigated in this article. The planned research aims to determine the best process parameter settings for obtaining the minimum taper and minimum heat affected zone for quality holes. The experimental investigation is performed utilising a Box-Behnken design-based response surface methodology (BRSM) and the influence of numerous input parameters (pulse frequency, cutting speed, lamp current, and air pressure) have been discussed by various surface plots and contour plots. The whale optimisation algorithm (WOA) is implemented to optimise the process parameters. Finally, confirmation tests are conducted to compare the experimental and optimal findings produced using the proposed methodology. The confirmation results prove that the WOA algorithm can be used for optimising the machining parameters with utmost supremacy. The sustainability assessment indicated that the projected process improves worker safety, creates a pleasant working environment, and improves product quality with an increased production rate.