This study evaluates the drilling performance of Syagrus romanzoffiana fiber-reinforced bio-epoxy biocomposites, focusing on reducing delamination for better industrial use. An experimental investigation was conducted on drilling composite laminates made by hand lay-up with 30% fiber content. The research examined how various factors—drill bit type (high-speed steel (HSS) and HSS coated with titanium nitride (HSS-TiN)), drill diameter ( d , 5–10 mm), spindle speed ( N , 800–1600 rpm), and feed rate ( f , 50–150 mm/min)—influenced delamination damage, measured by the delamination factor ( F d ) through digital image analysis. Predictive models for F d were created using Response Surface Methodology (RSM) and an Artificial Neural Network (ANN). Results showed that the ANN model had higher predictive accuracy ( R 2 > 0.966, root mean square error (RMSE) < 0.032) than the quadratic RSM model. The analysis identified f as the most influential factor on delamination, followed by d . Additionally, HSS-TiN tools outperformed standard HSS bits. Optimization using a desirability function produced minimum F d values of 1.02319 for HSS-TiN and 1.03199 for HSS at an f of 50 mm/min, N of 1419.49 rpm, and d of 10 mm. The RSM model was confirmed to be statistically significant through analysis of variance ( p < 0.0001), which also revealed a notable interaction between f and N . These results indicate that the hole quality achievable in this biocomposite matches or surpasses that of carbon fiber-reinforced polymer and glass fiber-reinforced polymer under comparable dry drilling conditions. This evidence supports its potential for use in industries such as automotive, sporting goods, and non-critical aerospace components.
Ferfari et al. (Mon,) studied this question.