Effects of Drilling Conditions, Drill Material and Point Angle on Acoustic Emission and Hole Exit Delamination in Drilling Advanced Fiber Reinforced Composites


A 1/3 fractional factorial design of experiment with four factors at three levels was used to investigate drilling of multi-directional AS4/PEEK composites. The design of experiment was conducted to determine the main effects and two factor interactions of drill point angle, cutting speed, feed rate, and drill material on acoustic emission generated in drilling and drilled hole exit delamination. Drill material, feedrate, cutting speed, and drill point angle were found to have statistically significant effects on total and average acoustic emission energy generated which also depends on the location of the acoustic emission spectra (on the workpiece or on the drilling fixture). Drill material was found to have the most significant effect on exit hold delamination, and accounted for over 50% of the variation in the measured exit hole delamination. Carbide drills were found to produce the least amount of exit hold delamination throughout the range of speeds investigated followed by Polycrystalline Diamond drills, while High Speed Steel Cobalt drills were found to produce holes with the greatest amount of exit hold delamination.

Meeting Name

Process Control and Sensors for Manufacturing II


Mechanical and Aerospace Engineering

Document Type

Article - Conference proceedings

Document Version


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© 1999 SPIE -- The International Society for Optical Engineering, All rights reserved.

Publication Date

01 Jan 1999