Experimental analysis of drilling induced damage in aramid composites

Aramid composites are increasingly used alone or combined with other composites in structural and personal protections due to the current demand of these applications against ballistic or fragment hazards. Drilling is a common operation required prior to mechanical joining of components, however this operation has been poorly analyzed in the case of aramid composites. Drilling induced damage of this family of composites is analyzed in the present work considering the effect of the drill geometry and cutting parameters. Fuzzing was the dominant damage mechanism both at hole entry and exit being also found delamination in most cases. Drill geometry and feed were influential parameters on resultant composite damage. Main contribution of this work is the obtainment of phenomenological expressions derived from experimental data, allowing the prediction of damage extension as a function of cutting parameters.The authors acknowledge the Ministry of Economy and Competitiveness of Spain and FEDER program under the Projects: RTC-2015-3887-8, DPI2017-88166-R and DPI2017-89197-C2-1-R for the financial support of the work