Mathieson Andrew, Cardoni Andrea, Cerisola Niccolò, Lucas Margaret
IEEE Trans Ultrason Ferroelectr Freq Control. 2013 Jun;60(6):1126-33. doi: 10.1109/TUFFC.2013.2675.
Power ultrasonic applications such as cutting, welding, and sonochemistry often use Langevin transducers to generate power ultrasound. Traditionally, it has been proposed that the piezoceramic stack of a Langevin transducer should be located in the nodal plane of the longitudinal mode of vibration, ensuring that the piezoceramic elements are positioned under a uniform stress during transducer operation, maximizing element efficiency and minimizing piezoceramic aging. However, this general design rule is often partially broken during the design phase if features such as a support flange or multiple piezoceramic stacks are incorporated into the transducer architecture. Meanwhile, it has also been well documented in the literature that power ultrasonic devices driven at high excitation levels exhibit nonlinear behaviors similar to those observed in Duffing-type systems, such as resonant frequency shifts, the jump phenomenon, and hysteretic regions. This study investigates three Langevin transducers with different piezoceramic stack locations by characterizing their linear and nonlinear vibrational responses to understand how the stack location influences nonlinear behavior.
诸如切割、焊接和声化学等功率超声应用通常使用兰姆波换能器来产生功率超声。传统上，有人提出兰姆波换能器的压电陶瓷堆应位于纵向振动模式的节点平面内，以确保在换能器运行期间压电陶瓷元件处于均匀应力下，从而使元件效率最大化并使压电陶瓷老化最小化。然而，如果将诸如支撑法兰或多个压电陶瓷堆等特征纳入换能器结构中，在设计阶段这一通用设计规则往往会部分失效。同时，文献中也有充分记载，在高激励水平下驱动的功率超声设备会表现出与杜芬型系统中观察到的类似非线性行为，如共振频率偏移、跳跃现象和滞后区域。本研究通过表征三种具有不同压电陶瓷堆位置的兰姆波换能器的线性和非线性振动响应，来研究堆位置如何影响非线性行为。
