Burr Formation in drilling of aluminum plates under cutting conditions modelled for manual operation

Abstract Aluminum alloy is widely used in aircraft structural components. The high cutting force in the conventional machining often causes the burr formation in the machined parts. To overcome the problems, machining method with low cutting force are recommended. In this study, we attempted to mechanize the manual drilling (soft-machining) to establish a new drilling method with a small probability of burr generation. The thrust force in manual drilling is less than one-tenth of that in CNC machining. A total of more than 200 holes were drilled with the same drill at 35 to 110N of applied load. In the drilling of single plate, burr formation is related to the inclination of the drill exit surfaces. Even in the drilling of stacked plates, the soft-machining can drill the through holes at the specified points in all conditions. In the soft-machining, the level of load P[N] becomes an important parameter to minimize the damage generation and it may be a mandatory to adjust the load to the minimum level required for cutting and tool feed. Applying soft machining to robotic drilling may solve vibration problem.