Abstract:The ultrasonic transducer is the core component of an ultrasonic vibration-assisted cutting device. To develop a large-amplitude ultrasonic vibration-assisted cutting device suitable for high-speed dry cutting, the first step is to design and develop the ultrasonic transducer. Based on the design method of the second-stage amplified ultrasonic transducer considering the tool, following the integrated design concept of amplifier-ultrasonic transducer, and combined with the results of modal analysis and harmonious response analysis using ANSYS finite element software, a two-stage amplified ultrasonic transducer was designed and developed. According to the characteristics of the developed two-stage amplified ultrasonic transducer, its matching ultrasonic generator, anti-rotation ring, power transmission system, and tool holder shell structure were systematically designed and developed. Performance tests including impedance analysis and amplitude measurement were carried out for the developed two-stage amplified ultrasonic transducer. Experimental test and analysis of the designed and developed large-amplitude ultrasonic vibration-assisted high-speed dry cutting device were conducted to explore the improvement of surface quality in the difficult-to-machining material 30CrMnSiNi2A. The results show that the longitudinal ultrasonic vibration simulation results of the two-stage amplified ultrasonic transducer are consistent with the theoretical design, and the longitudinal vibration amplitude output is stable. The longitudinal vibration amplitude is 15.4 μm at 50 % output power and can reach a maximum of 25.1 μm, with the output amplitude positively correlated with the power percentage, indicating good performance test results. The developed large-amplitude ultrasonic vibration-assisted cutting device greatly reduces the cutting force and surface roughness in the feeding direction, significantly improves the surface quality of difficult-to-machine materials, and is suitable for high-speed dry cutting of such materials.