Dynamic analysis on drilling of aluminum matrix composite of silicon carbide with cryogenically treated tools

Drilling of aluminum matrix composite of silicon carbide materials is analyzed using cryogenically treated drills under cryogenic conditions. Vibration acceleration, thrust force, geometrical aspects of drilled workpiece like hole quality, surface roughness, tribology properties of drill wear and chip morphology are evaluated at various drilling parameters such as spindle speed and feed rate. Experimental results showed that impact of spindle speed is considerably higher than impact of feed rate on vibration acceleration, whereas thrust force is influenced by spindle speed as well as feed rate. The maximum vibration acceleration obtained at the highest feed rate is 74.48 m/s2 and 81.34 m/s2 at the spindle speed of 3,000 rpm and 4,500 rpm. The hole diameter variation is 0.139 mm than original drill diameter and observed entry side hole diameter is slightly larger than that of exit side. Moderate spindle speed i.e., 3,000 rpm and 4,500 rpm produced better geometrical aspects of drilled workpiece and it is recommended for smooth drilling operation under cryogenic drilling condition. Adhesive wear is found to be prominent specially at the higher spindle speed. Smaller and smooth chips are observed at the lower spindle speed while short and curly shape chips are found at higher spindle speeds.