“三明治”结构强度弱化的反射特性研究  

Research of reflection characteristic with strength weakening in “sandwich” structures

作　　者：艾春安[1] 刘瑜 徐志高[1] 李剑[1] 

机构地区：[1]第二炮兵工程大学,西安710025

出　　处：《应用力学学报》2013年第2期179-183,300,共5页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金(51075390)

摘　　要：针对铝-胶层-铝结构强度弱化的超声检测问题,采用改进全局矩阵法推导了多层粘接结构中超声传播方程,通过降低胶层的剪切波波速来模拟粘接强度弱化,对不同频率、不同入射角情况下超声纵波入射"三明治"结构时的反射系数与粘接强度的关系进行了仿真计算。仿真结果为:超声纵波以0.5MHz入射,在入射角为65°～73°区域内进行扫描检测,通过角度分辨的方式对强度弱化区域进行定位。第一层与胶层之间的界面出现强度弱化时,检测条件为0.5MHz、65.9°的超声纵波;胶层与第三层之间的界面出现强度弱化时,检测条件为1.0MHz、62.9°的超声纵波。结果表明:在特定的频率和入射角进行组合情况下,采用超声纵波斜入射方法可实现对粘接结构界面的强度弱化区域的定位和粘接强度的定量检测。Aiming at the problem of ultrasonic test on strength weakening in aluminum-adhesive-aluminum structures,ultrasonic propagation equations in multilayer bonded structures have been achieved by employing improved global matrix.Strength weakening in bonded layer has been simulated by the decline of its shear velocity.The relationship between reflection coefficient and bonded strength has been calculated in different frequencies and incidence angles for longitudinal wave incident into 'sandwich' structures.The results of simulation are that the interface with strength weakening can be orientated by angular resolution at the frequency of 0.5MHz and the incidence angle of 65°～ 73°.The condition for testing first interface with strength weakening is ultrasonic longitudinal wave at the frequency of 0.5MHz and incidence angle of 65.9°,and the condition for testing second interface with strength weakening is ultrasonic longitudinal wave at the frequency of 1.0MHz and incidence angle of 62.9°.The results obtained indicate that quantitative test of bonded strength and orientation of the domain with strength weakening can be implemented by the method of ultrasonic longitudinal wave oblique incidence.

关 键 词：改进全局矩阵 强度弱化 反射系数 定量 定位 

分 类 号：O426.2[理学—声学]