Effect of cutting parameter on tool wear of HSS tool in drilling of Kevlar composite panel

The paper reports the tool wear in the drilling of composite panel in various cutting conditions. The drilling process was applied to 4mm thickness Kevlar composite panel by using HSS drill tool (2 flutes, 12 mm diameter, 17 mm length and 118° drill point angle). The process was conducted by using a vertical machining center. The tool wear was measured by using an optical microscope with the max precision 0.01 µm. The drilling process was conducted with a constant feed rate (75 mm/min) and three levels of spindle rotation speeds (1000, 3000 and 5000 rpm). Each cutting condition was applied to two different drill tools. In order to investigate the wear rate, the tool wear was measured in several levels of cutting time (i.e., after drilling of 5, 10, 20 and 30 drill holes). The result of the experiment shows that the cutting speed gives significant effect to the tool wear of HSS drill tool when drilling Kevlar composite panel. Higher cutting speed produced higher tool wear at any cutting time level. The result of the experiment also shows the effect of continuous / discontinuous cutting. Higher tool wear was found in a direct 20 holes drilling, compare to paused drilling (i.e., start with 10 holes, pause for 20 minutes then continue with other 10 holes).