Machinability investigations on high-speed drilling of aluminum reinforced with silicon carbide metal matrix composites

In this work, the research efforts have been made to investigate the effect of important drilling parameters such as spindle speed and feed rate on effectiveness of process and quality of holes during drilling of difficult-to-machine Al/SiC metal matrix composite using diamond-coated cemented carbide tool. Thrust force, hole diameter, delamination factor, surface roughness, tool wear, and chip analysis of the drilled holes were investigated at different spindle speeds (3000–9000 rpm) as well as feed rates (0.05–0.2 mm/rev), respectively. The outcomes of this study reveal that thrust force varies directly with the feed rate, but inversely with the spindle speed. Both the hole diameter and the delamination factor shows a rough proportionality with the feed rate, although the rates of variation are slow at the high spindle speed combined with a high feed rate. Similarly, the hole surface roughness increases with the feed rate, while the moderate spindle speeds produce better surface roughness. Smaller chips were found for all spindle speed. Adhesive and abrasive wear mechanisms are prominent on drill bit and drill wear occurs on both drill tip and secondary cutting edge. Drilling at moderate spindle speeds of 5000 rpm and 7000 rpm is the most suitable for the hole drilling in the Al/SiC metal matrix composites.