Ultrasonic vibration–assisted chatter suppression for deep hole boring of stainless steel

Due to the low rigidity of the boring bar with a large length-to-diameter ratio, chatter easily occurs during deep hole boring. In this paper, an ultrasonic vibration boring bar with a length-to-diameter ratio greater than 10 is designed to suppress the chatter during the boring operation of deep holes. First, the dynamic model of the boring operation is built to guide the design of the ultrasonic vibration boring bar. Then, the optimal design of structure parameter of the ultrasonic vibration boring bar is performed by the finite element method, and then the optimized boring bar is manufactured. Finally, the vibration performance test and cutting experiments are carried out to verify the machining capability of the bar. The experimental results show that the ultrasonic vibration boring bar can reduce the cutting force by about 35%, improve the system stability, and increase the quality of the relative machined surface by about 43%, which demonstrate the feasibility of chatter suppression of the developed ultrasonic vibration boring bar.