Effect of Twist Drill Geometry and Drilling Parameters on Hole Quality in Single-Shot Drilling of CFRP/Al7075-T6 Composite Stack

Drilling two different materials in a layer, or stack-up, is being practiced widely the aerospace industry to minimize critical dimension mismatch and error subsequent assembly process, but compatibility of drill compensate differing properties composite still major challenge industry. In this paper, effect customized twist geometry drilling parameters are investigated based on thrust force signature generated during CFRP/Al7075-T6. Based ANOVA, it found that maximum for both CFRP Al7075-T6 highly dependent feed rate. Through analysis force, supported by hole diameter error, surface roughness, chip formation, optimum tool selection includes helix angle 30°, primary clearance 6°, point 130°, chisel edge speed 2600 rev/min rate 0.05 mm/rev. The obtained study benchmarked against existing practice capability produce higher quality efficiency, which set at 0.1 mm/rev