Investigation of the Effect of Cutting-Edge Rounding on Surface Quality in Milling of Al 7075 and Al 6082 Alloys

Al 7075 and Al 6082 alloys are alloys that are widely used in many sectors, especially aviation and automotive. During their processing along with the widespread use of those alloys, significant machinability problems such as low surface quality due to chip accumulation (Built Up Edge-BUE) on the cutting edge are observed. In this study, the effect of cutting-edge corner rounding and machining parameters on surface roughness in milling of Al 7075 and Al 6082 alloys were experimentally investigated. To determine the effect of cutting-edge rounding, two different corner rounding values (5.5-6 µm and 7-9 µm) were applied and compared with standard/coated and standard/uncoated tools in terms of machining performance. In the experimental studies, cutting parameters were determined as two different cutting speeds (300 m/min, 400 m/min) and two different feed rates (0.085 mm/tooth, 0.11 mm/tooth). With each tool, peripheral milling was performed on four sides of the prismatic test specimens under dry machining conditions. Taguchi L8 orthogonal array experimental design was used as the experimental design. Analysis of variance (ANOVA) was performed to evaluate the effects of cutting parameters on surface roughness and the reliability of all results was above 85%. The results of the analysis of variance revealed that the alloy type was more effective on the surface roughness. In the surface roughness measurements, the best surface roughness values (Ra=0.14 µm) were obtained in the experiments performed with a standard/coated cutting tool using a cutting speed of 300 m/min and a feed rate of 0.11 mm/tooth.