Longitudinal Ultrasonic Machining System Design and Ultrasonic Milling Process Characteristics of Carbon Fiber Honeycomb Composites

ABSTRACT Advanced milling technology is the key to achieving high‐quality and efficient processing of carbon fiber honeycomb composites (CFHC). To improve the surface quality, the longitudinal ultrasonic composite horn and ultrasonic toothed disc cutter were designed to meet the requirements of machining accuracy. An analysis was conducted on how the geometric parameters of an ultrasonic toothed disc cutter affected the modal characteristics and resonant frequency of a longitudinal ultrasonic machining system. The results showed that as the diameter of the tool and the wedge angle diminished, the resonant frequency of the ultrasonic toothed disc cutter rose. Conversely, an increase in the thickness of the tool led to a reduction in resonant frequency. When configured with a wedge angle of 14°, a thickness of 2 mm, a diameter of 96 mm, and comprising 36 teeth, the ultrasonic toothed disc cutter met the resonant frequency requirements of the longitudinal ultrasonic machining system. Compared to conventional milling, the cutting force of longitudinal ultrasonic‐assisted milling (LUAM) was reduced by 25.64%, the surface roughness of double wall and single wall was reduced by 33.43% and 35.11% respectively, and tear quantity was reduced by 43.75%. The designed longitudinal ultrasonic machining system provided important theory and guidance for the realization of advanced milling.