Resonant Tuning of Langevin Transducers for Ultrasonically Assisted Machining Applications

This article provides a fundamental study into the trade-offs between the location of piezoceramic elements, resonant frequency, and achievable ultrasonic vibration amplitude at the working end of the bolted Langevin-style transducers (BLTs) for ultrasonically assisted machining (UAM) applications. Analytical models and finite-element (FE) models are established for theoretical study, which are then validated by experiments on four real electromechanical transducers. The results suggest that resonant frequency and oscillation amplitude of the BLTs depend essentially on the dimensions of the system and the location of the piezoceramic elements. The highest resonant frequency and the maximal vibration are achieved when the piezoceramic elements are at the longitudinal displacement node, where the highest effective electromechanical coupling coefficient value is exhibited. However, the minimal resonant frequency and the lowest vibration, which is almost equal to zero, are observed when the piezoceramic elements are located at the displacement antinode. In addition, the longitudinal displacement node locations are dependent on the resonant frequency of the devices rather than the locations of the piezoceramic elements.