Research on ultrasonic longitudinal-torsional shank based on the giant magnetostrictive material

The application of ultrasonic longitudinal-torsional (LT) machining in the field of machining brittle and hard materials such as ceramics and titanium alloys has been increasingly emphasized. Aiming at the existing ultrasonic LT shank, mainly using piezoelectric materials resulting in low power density, overheating failure, and small torsional vibration components, a new ultrasonic LT shank based on giant magnetostrictive materials is designed. The conical transition hollow horn and giant magnetostrictive ultrasonic LT transducer are designed by theoretical analysis method, and the effects of different spiral groove parameters on the resonant frequency and torsion-longitudinal ratio of the horn are analyzed by using finite element software, and the modal analysis is carried out for the shank. Finally, the ultrasonic LT shank is subjected to experimental studies on impedance characteristics, frequency amplitude response, and voltage amplitude response, and the simulation and experimental results show that the designed shank has a resonant frequency of 19.12kHz, a maximum longitudinal amplitude of 14.5 mu m, a maximum torsional amplitude of 6.1 mu m, and a maximum torsion-to-longitudinal ratio of 0.46, which is suitable for most of ultrasonic machining, and verifies the correctness of the design methodology.