三层介质超声谐振模式随材料和界面粘接性能变化的演变规律  

Evolution of the ultrasonic resonance modes in a three-layer structure with change of material and interface adhesion properties

作　　者：刘婧[1] 徐卫疆 胡文祥[1] 

机构地区：[1]同济大学声学研究所,上海200092 [2]Institut d'Electronique de Microelectronique et de Nanotechnologie UMR CNRS 8520, Departement Opto-Acousto-Electronique, Universite de Valenciennes, Valenciennes 59313, France

出　　处：《物理学报》2016年第7期203-214,共12页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11374230)和国家自然科学基金重点项目(批准号:10834009)资助的课题~~

摘　　要：在用超声波谐振对粘接材料的粘接强度进行无损评估时,不同模式对粘接强度的敏感程度受到众多因素和参数的影响,对检测结果的可靠性至关重要.基于多层介质中声传播和界面弱粘接边界条件的理论模型,将一个上下非对称的金属-粘接剂-金属三层结构的平面波反射系数函数中的谐振模式看作是上下铝金属层各自的Lamb波频散模式通过夹心粘接剂层相互耦合后叠加组成.改变影响结构粘接强度的因素,即粘接剂的性能参数(声阻抗、密度、厚度)和界面切向劲度系数kt来分析三层结构谐振模式耦合方式的变化,得出结论:粘接结构粘接性能的变化基本上不改变与被粘铝层相关的固有部分的Lamb波模式,而它们的耦合模式则在谐振频率上产生平移并会与固有模式进行交换和替代;不同参数的变化引起的模式演变有各自的规律,大多可彼此区分.The quantitative non-destructive evaluation（NDE） of interface adhesion has long been a challenge for the safe use of bonding structures. It is difficult to predict the adhesion resistance force between adhesive and adhered material without performing destructive testing. Ultrasonic approach seems to be the only potential way for its NDE based on the reason of mechanical nature of the problem.Different ultrasonic techniques, such as bulk wave echography, reflection resonance, and Lamb guided waves, have been used to evaluate the interface adhesion strength. But no direct relation between the interfacial bonding strength and the ultrasonic measurement has been established. The most used compression wave echography and resonance at normal incidence are less sensitive to the interface condition, except for a disbond. It is essential that the interface should be excited with a shear stress component to increase the measurement sensibility. But it is not easy to excite the interface by using shear waves in experiment, while the use of guided waves will encounter the problems of high attenuation and mode selection as all modes are not sensitive to a certain interface in a bonded structure.A previous study has shown that the V（z） inversion technique can be used to perform a multimode measurement on a layered structure, where both compression and shear stress resonance occur. This method has the advantage in using a simple experimental setup working at the normal incidence with a focus transducer of large angular aperture.The inversed angular-frequency reflectance function R（θ, f） gives the resonance modes which are equivalent to the Lamb type guided modes, while it is a local determination of the wave mode, thus the difficulty in guided wave measurement above mentioned can be avoided.The first part of the paper contains the development of the theoretical model for wave propagation in a multilayered structure where three-layer sandwich bonded structures can be considered as a particular case. A weak interfaci

关 键 词：粘接结构 界面粘接强度 声反射谐振函数 模式频散 

分 类 号：O426[理学—声学]