A novel approach for characterization of delamination and burr areas in drilling FRP composites

Abstract

Drilling of aerocomposites is very critical process in the production of aviation components. The defects in the drilled holes can lead to high stresses on the rivet and the component and thus, catastrophic failure of the structure. The economics of drilling-induced defects is significant, particularly considering the various stages related to the part as it reaches the final assembly line. In this study a novel, simple, inexpensive, and accurate AutoCAD Image Processing (ACIP) technique was developed to evaluate the damaged area in drilling FRP composites. Drilling operations are performed on woven GFRP composites without back-up plate. Scanning electron microscopic examination was conducted on representative specimens to clarify the different mechanisms of chip and burr formation with respect to fiber orientation and the instantaneous velocity vector of the cutting edge. The results revealed that the developed ACIP technique has an amazing accuracy without missing any details in the computed delamination and burr areas in comparison with the other methods. Because of the non-dimensional delamination parameters are not account the damaged area, in some cases they seems to be not suitable for representing the measured values, which considerably increased the importance of this study.