Ding Wenxiang, Bavencoffe Maxime, Lethiecq Marc
GREMAN UMR7347, Université de Tours, CNRS, INSA-CVL, 3 Rue de la Chocolaterie, 41000 Blois, France.
Materials (Basel). 2021 Apr 27;14(9):2269. doi: 10.3390/ma14092269.
Ultrasonic transducers performance can be seriously deteriorated by loss of adhesion between some constitutive elements such as the active element, the backing, or the matching layer. In the present work, the influence of bonding delaminations on the performance of a single-element ultrasonic transducer, which is composed of a piezoelectric disk, a backing, and a matching layer, is studied numerically and experimentally. Based on the positions between layers, two cases, i.e., delaminations between ceramic and backing or between ceramic and matching layer, are considered. Each case involves three different types of delaminations, which are marked as delamination type (DT)-I, II, and III. DT-I, a circular shape delamination, starts from the center and expands towards the peripheric zone; DT-II, an annular shape delamination, starts from the peripheric zone and expands towards the center; DT-III is a sector shape delamination with a given angle. The numerical simulations are performed by the finite element method and the influence of delaminations on the electromechanical admittance (EMA) of the transducer is investigated. 3D printed backings and matching layers are mounted on a PZT sample to assemble delaminated single-element transducers. An impedance analyzer is used for experimental measurements. Comparison between numerical and experimental results shows a reasonable agreement making changes in EMA an interesting indicator to inform about the occurrence and severity of delaminations in a single-element ultrasonic transducer.
超声换能器的性能可能会因一些组成元件（如有源元件、背衬或匹配层）之间的附着力丧失而严重恶化。在本工作中，对由压电圆盘、背衬和匹配层组成的单元素超声换能器中粘结分层对其性能的影响进行了数值和实验研究。基于各层之间的位置，考虑了两种情况，即陶瓷与背衬之间或陶瓷与匹配层之间的分层。每种情况都涉及三种不同类型的分层，分别标记为分层类型（DT）-I、II和III。DT-I是一种圆形分层，从中心开始并向周边区域扩展；DT-II是一种环形分层，从周边区域开始并向中心扩展；DT-III是具有给定角度的扇形分层。通过有限元方法进行数值模拟，并研究分层对换能器机电导纳（EMA）的影响。将3D打印的背衬和匹配层安装在PZT样品上，以组装分层的单元素换能器。使用阻抗分析仪进行实验测量。数值结果与实验结果的比较表明两者具有合理的一致性，这使得EMA的变化成为一个有趣的指标，可用于了解单元素超声换能器中分层的发生情况和严重程度。
