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Increasing aircrafts' productivity and reducing their riveting time have created the need of one-shot drilling of dissimilar materials. The present work had followed this strategy on 4 shaft satin weave carbon fiber and epoxy matrix (AS-4 woven CFRP) and aluminum alloy (AA 2189) in order to study the effect of drilling direction on Al and carbon fiber reinforced polymer thrust force evolution and holes' quality. It presents a comparison between CFRP, CFRP/Al, and Al/CFRP results using the same drilling tool and cutting parameters to understand the influence of adding metal layers on CFRP drilling defects. It was observed that the increase of the thrust force is related to cutting parameters. It causes thermal degradation of composite matrix when drilling CFRP/Al, and it impacts the aluminum surface roughness. One-shot drilling strategy does not affect thrust force evolution whenever the layers' position in the stack. Drilling defects exist especially in the composite part such as uncut fibers, chipping, and spalling. It was found that the cutting speed had the dominant influence on surface damage. Holes' quality differs from one configuration to another. Adding Al layer on the top reduces seriously the composite drilling defects and causes groove in the Al holes. Composite matrix smearing was observed when drilling CFRP/Al. It seems that drilling CFRP sheet between to supports improves composite holes' quality.

The main purpose of composite materials drilling is the need to put together different parts of a structure, in aeronautics for example. The objective of this study is to experimentally analyze the influence of drilling on a carbon/epoxy composite. Three geometries of drill, a range of cutting speed and feed have been tested. Thrust forces and moments have been recorded during machining and macroscopic analyses have been conducted to examine outside and inside surfaces of the holes. Damages have been also quantified using delamination factor Fd. Experimental results have shown significant influences of feed and drill geometry on delamination and the best results have been obtained using a spur drill.

The evolution of carbon/epoxy composites use in aeronautics requires a better comprehension of the machining conditions influence on these materials. This study aim is to establish, based on the experimentation, the relationship between machining conditions and the behavior of drilled 2D and 3D carbon/epoxy composites. Two drill geometries, seam introducing and a range of cutting speed and feed have been tested. The effect of each parameter has been assessed in terms of thrust force, moment (recorded during machining) and defects (performed by macroscopic analyses and quantified using delamination factor Fd). Experimental results have shown significant influences of feed and drill geometry on delamination reduction. The use of a spur drill and a low feed generates minor defects and produces the best results. Furthermore, stitching helps reduce damage inside the hole.