Machining aerospace aluminium alloy with cryo-treated and untreated HSS cutting tools

In this study, effects of drilling parameters and cryogenic treatment, which were applied to the cutting tool (M35 HSS drill bit), on the burr width, surface roughness (Ra), chip formation and tool wear were investigated in drilling of AA2024-T3 aluminium alloy under dry drilling conditions. In this context, the drilling parameters determined based on the Taguchi experimental design were employed, and also, the analysis of variance (ANOVA) and regression analysis were performed. The spindle speed (1500, 3000 and 4500 rev/min), feed rate (100, 150 and 200 mm/min) and cutting tool (cryo-treated and untreated M35 HSS tools) were selected as machining parameters. In terms of average burr width, the performance of the cryo-treated (DC&T) HSS drill bit was 28.91% (for the highest value) and 46.96% (for the lowest value) better than that of the untreated (UT) HSS drill bit. According to Ra values, the performance of DC&T HSS drill bit was 13.29% (for highest value) and 12.01% (for lowest value) better than that of UT HSS drill bit. The flank wear (VB) of UT HSS drill bit was found to be approximately four times greater than the flank wear of DC&T HSS drill bit.