Experiments and simulations on ultrasonically assisted drilling

Ultrasonically assisted drilling (UAD) has received great interest in the past few years by both academia and industry. The technology has already demonstrated a multitude of advantages over conventional drilling technology although its use has been mainly thwarted by inconsistent results. In order to aid the further development of UAD, a better understanding of the underlying dynamical process is required. In this work, an investigation into UAD is performed. Longitudinal vibration is used to excite standard 8 mm high-speed steel drill bits and mild steel samples are used for cutting tests. A swept sine wave is used to excite the system whilst the cutting forces that result are acquired. Clearly optimal regions are revealed and these are discussed. Subsequent to the experimental investigation, three-dimensional finite element drill bit models are employed to further understand the drill bit's vibrational characteristic. The simulation results show new areas of interest in which further work is necessitated.