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.

中文翻译：

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用于超声辅助加工应用的兰格文传感器的共振调谐

本文为压电陶瓷元件的位置，谐振频率以及在用于超声辅助加工（UAM）的螺栓连接的Langevin型换能器（BLT）的工作端可达到的超声振动幅度之间的取舍提供了基础研究。建立了用于理论研究的分析模型和有限元（FE）模型，然后通过在四个实际机电换能器上进行的实验进行验证。结果表明，BLT的谐振频率和振荡幅度主要取决于系统的尺寸和压电陶瓷元件的位置。当压电陶瓷元件位于纵向位移节点时，可获得最高的共振频率和最大的振动，其中显示出最高的有效机电耦合系数值。然而，当压电陶瓷元件位于位移波腹处时，观察到最小共振频率和最低振动，几乎等于零。另外，纵向位移节点的位置取决于器件的谐振频率，而不是压电陶瓷元件的位置。