Thrust force model for vibration-assisted drilling of aluminum 6061-T6

Vibration assistance has increasing applications in metal removal processes. This method induces high-frequency and low-amplitude vibration in the feed direction during cutting, and has the potential to reduce cutting forces leading to improved surface quality and reduced tool wear. Note that this cutting process is distinct from ultrasonic machining. This paper presents a thrust force model to predict the thrust force during vibration-assisted drilling of aluminum 6061-T6. This model incorporates plowing force and strain rate-dependent shear strength to provide more accurate predictions than the existing model. The results of 72 drilling experiments with TiN-coated standard twist drills are reported. The predictions from the developed thrust force model are compared with the experimental results. The comparison demonstrates that the maximum deviation between the predictions and the averaged values of the experimental measurements is 20% using the existing model and only 7% using the proposed model. (C) 2009 Elsevier Ltd. All rights reserved.