Orbital Drilling of Aerospace Materials

Orbital drilling is a holemaking process by milling, in which the center of an end mill orbits around the center of the hole while spinning on its own axis and moving in the axial direction. Compared with conventional push drilling, it significantly reduces the thrust force and creates non-continuous chips. Orbital drilling can reduce burr size when machining metals and reduce fiber delamination when machining carbon fiber reinforced plastics (CFRP). Due to the high quality holes generated no clean-up or disassembly/reassembly is needed. Also, less tool inventory is needed using orbital drilling since one tool can be used for different diameter holes. This paper presents a study of machining dynamics of orbital drilling and tooling solutions for orbital drilling of aerospace aluminum alloy, titanium alloy, and CFRP materials.