Aluminum has the widest usage areas. These include light armored vehicles for the defense industry, marine vehicles, aircraft, automobile sheets and engine blocks, and many industrial machinery parts. In the experimental study, Al 7xxx series was preferred due to its heat treatment. Al-7075 material was subjected to drilling tests on a CNC milling machine under dry-cutting conditions. Experiments, carbide drill bits, 8 mm, 10 mm, 12 mm. It was made using the appropriate number of revolutions, different advances, and different tip angles for their diameters. The structure and conditions of chips formed in processes with different geometries were examined. Chip forms were examined for 9 different experiments with tools with different geometries and different cutting condition combinations. In machining, cutting speed (Vc), feed (f), and harmony are important. Accordingly, cutting speed and feed in chip forms could not be examined independently of each other. The change in chip forms was evaluated according to the feed rate (Vf), which is a combination of these two cutting parameters. According to the experimental results, as the progress increased, a tendency towards continuous chips towards discrete chips was observed. It was observed that as the cutting speed increased, the chip turned from discrete to continuous. As the drill diameter increases, broken and discontinuous chip formation is observed. While the cutting speed (V) was kept constant in the experiments, the feed rate (f) and drill tip angle (ɵ) parameters were changed within certain limits and the surface roughness and chip formation of these factors were examined. Chip forms of 7075 Al alloys after machinability are grouped into four groups. Mixed, strip, and Chip forms obtained in an auger and helical forms are grouped as acceptable and unacceptable. Except for the helical chip form, it was considered as undesirable chipes forms. While finishing processes were extremely suitable in terms of surface quality for acceptable chip forms, the surface qualities obtained for other chip forms were observed to be at a very low level. ORCID NO: 0000-0001-7076-77661
Anahtar Kelimeler: Al 7075, Drill Geometry, Surface Roughness, Machinability, Chipes Formation
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