Parametric study of CO2 laser drilling of carbon nanopowder/vinylester/glass nanocomposites using design of experiments and grey relational analysis

Research efforts are concentrated on improving the quality of laser drilled holes in thermoset based composites. Heat affected zone is one of the major quality factors in laser drilled holes of polymer composites. One of the promising methods to reduce heat affected zone is to disperse thermally conductive nanofillers in polymer composites to improve the heat transfer characteristics during laser drilling. The objective of this research was to investigate the effect of carbon black along with laser parameters such as laser power, pulse frequency and scanning speed on the heat affected zone and taper angle of laser drilled holes based on L16 orthogonal array lay-out. Both heat affected zone and taper angle significantly reduced with the addition of carbon black. The results showed that heat affected zone is reduced by employing lower laser power and taper angle is reduced by adopting higher laser power. Grey relational analysis was used to identify the optimal combination of laser drilling parameters for multiple responses. Multiple regression models were developed for predicting heat affected zone and taper angle.

► CO2 laser drilling on (0–6 wt%) carbon black/vinylester/glass were performed. ► Addition of carbon black and lower duty cycle reduced the HAZ and taper angle. ► Carbon black contributed 83.5% for minimizing HAZ and taper angle. ► Accurate prediction of HAZ and taper angle were made using linear regression model.