Influence of Thermal Effects on Hole Quality in Dry Drilling, Part 1: A Thermal Model of Workpiece Temperatures

Abstract

A finite element thermal model is devised to capture the transient temperatures in the workpiece in drilling. Experimental observations along with an inverse heat conduction procedure is utilized in identifying the strength of the heat fluxes from the three distinct regions of the drill (drill body, cutting lips and chisel edge) at various process conditions in both wet and dry conditions with coated and uncoated drills. The identified heat fluxes along with a calibration scheme are used in predicting the transient temperatures in the workpiece in both dry and wet conditions. The model demonstrates the ability to predict the temperatures within 20 percent of the measured temperature rise.