A Tool Life Prediction Model Based on Taylor's Equation for High-Speed Ultrasonic Vibration Cutting Ti and Ni Alloys

A high-speed ultrasonic vibration cutting (HUVC) method has been proposed for the precision machining of Ti and Ni alloys with high efficiency and fine surface quality in recent years. During the HUVC, the tool life can be enhanced significantly at a relatively high cutting speed. The effective cooling due to the tool-workpiece separation resulting from the ultrasonic vibration is regarded as the primary reason for these advantages. In order to figure out the influences of effective cooling and ultrasonic vibration for further understanding of the mechanism of HUVC and guidance of practical engineering, a quantitative relationship between the tool life and cutting conditions (including cutting, ultrasonic and cooling parameters) needs to be built. Therefore, in this paper, a tool life prediction model based on Taylor's equation was established. Both the cooling contribution during the separation interval and tool impact resulting from the ultrasonic vibration were added to be considered. Then, experiments were conducted and the results showed that the separation effect with effective cooling was the main reason for the considerable benefits of HUVC. Although the impact was inevitable, high-speed, stable cutting regions of Ti and Ni alloys could still increase to 200-450 and 80-300 m/min, respectively. The prediction model could be used to optimize the cutting parameters and monitor the machining process according to the actual machining requirements.