矩阵理论在黏接结构界面脱黏超声检测方法中的应用

Application of Matrix Theory in Acoustic Testing Method for Interfacial Debonding of Adhesive Structure

黏接结构界面脱黏的超声检测与评价是一个有难度的前沿性课题.基于传递矩阵方法并将脱黏界面层假定为流体薄层,推导了体波入射下具有流-固(气-固和液-固)耦合界面的脱黏结构中声反射与透射系数表达式.将该方法应用于两层结构并与已有结果对比验证了所推公式的正确性.研究了声波入射角度、频率的变化对具有刚性联接界面的黏接结构和具有流-固耦合界面的脱黏结构中体波传播特性的影响.结果表明,体波在多层结构中的传播模式主要依赖于入射角度、频率等参数.若声波的入射角度和频率取值适当,可以将刚性联接、气-固以及液-固耦合界面进行区分.

It is a difficult and challenging subject for ultrasonic inspection to test and evaluate the debonding interface of adhesive structure.Assuming,the debonding interface layer to be a fluid thin layer,the acoustic reflection and transmission coefficient expressions were derived based on the transfer matrix method for the body waves striking debonding structure with fluid-solid（gassolid and liquid-solid）coupling interfaces.Firstly,this method was applied to a two-layered structure and the correctness of the method was verified by comparing with the existing results.Then,the influences of the incident angle and frequency changes of the acoustic wave on the body wave propagation characteristics were analyzed for adhesive structure with rigid interfaces and debonding structure with fluid-solid coupling interfaces.The results show that the propagation modes of the body waves in the multilayered structure mainly dependent on the incident angle,frequency and other parameters.The rigid interfaces,gas-solid and liquid-solid coupling interfaces can be distinguished in the case of the incident angle and frequency of the acoustic wave are appropriate.The research results provide a theoretical reference for identifying the adhesive interface debonding with ultrasonic spectrum technique.