Multi-objective optimization analysis of cutting parameters when drilling composite materials with special geometry drills

Abstract

The cutting tool geometry is strongly influencing damage induced during drilling of composite materials. The searching of new and optimum geometries reducing the damage on the laminates is still a challenge for the scientific community and industry. This study focuses on drilling woven CFRP laminates with four different tool geometries, analyzing the influence of the cutting parameters on the cutting forces and delamination damage. The work is divided in three phases; the first phase carries out a full factorial design of experiments conducted to quantify the significance of each process parameter as well as its interaction, on the generation of delamination at the hole entry and exit as well as the thrust force and torque. The second phase uses the response surface methodology (RSM) to establish the relationships between each output variable and the input variables based on ANOVA results. Finally, a multi-objective optimization strategy has been presented using the fitting equations to select optimum ranges of design parameters that can minimize collectively the aforementioned output variables. Ultimate objective is the process improvement toward negligible defects during drilling of woven CFRP composites.