A new burr formation model for drilling with tool wear

This paper presents a new burr formation model for predicting drilling burr sizes in consideration of tool wear. A new force model is established by combining the drilling thrust force with the ploughing force caused by tool wear. The traditional drilling burr formation model is modified by using the new force model to determine burr heights and thicknesses in terms of tool wear percentage. A series of drilling experiments are carried out on two commonly used aerospace aluminiums to validate and calibrate the model. A close agreement between simulation and experiment is achieved showing that burr height and thickness increase with the increase in tool wear, and at 50% of tool wear, the maximum burr height could triple and the maximum burr thickness could double.