Prediction of drilling temperature during low-frequency vibration drilling of titanium alloy

Low-frequency vibration drilling can suppress the drilling temperature and extend tool life. In low-frequency vibration drilling, there are drilling times and non-drilling times in each vibration cycle. A past study clarified that the temperature increases during drilling, and the peak temperature in one vibration cycle is nearly equal to a conventional drilling temperature, but the temperature of the drill corner decreases during non-drilling periods. However, the relationship between the amount of temperature increase/decrease during intermittent drilling and the vibration and drilling conditions and temperature change near the cutting edge has not yet been clarified. In this study, to determine the drilling temperature during the drilling and non-drilling periods of low-frequency vibration drilling, the temperature near the cutting edge was measured experimentally by an embedded K-type thermocouple. To identify the optimum conditions for low-frequency vibration drilling without repeating the experiment, the temperature transition of the cutting edge was simulated based on the heat input caused by the cutting energy, calculated from the principal cutting force and speed. To simulate the temperature change of the drill edge, the principal force acting on the cutting edge was calculated from two-dimensional cutting data. A comparison of the experimental and simulated temperatures showed that the simulated temperature transition agreed well qualitatively with the results measured during low-frequency vibration drilling.