Modelling of temperature distribution in the work material during drilling under sustainable environment

Abstract

The knowledge of temperature distribution on the work material is essential to incorporate various sustainable techniques like dry and near dry machining. A new approach of the thermal model during dry drilling process has been established to predict the magnitude and distribution of machining-induced work material temperature. Here the classical heat source method was adopted. In the present work the contact point between the cutting edge of the drill tool and the work material is represented as a line heat source inclined at an angle, moving with a velocity. The temperature rise due to chip clogging, built-up edge formation and friction is neglected in the present model. The plots from the investigation revealed that the temperature increased with higher values of Peclet number which is a representation of the relative velocity of the heat source and the thermal properties of the conduction medium. Also, it is observed that the angle of inclination of heat source has little influence on the temperature rise at lower velocity. The model provides a cohesive basis to deal with the temperature rise in the workpiece during the dry drilling process. By using the model temperature distribution at any point on the work material can be obtained. To validate the analytical results experiments were carried keeping the cutting speed constant and varying the feed rate to measure the work material temperature rise using an infra red camera. The measured temperature during the experiment was found to be higher than the predicted temperature since some of the relevant factors like built-up edge formation, chip clogging and increase in friction were not considered in the model. Also further investigation is necessary to find the influence of point angle on the developed model.