异形截面复合材料构件高速超声检测技术

Rapid Ultrasonic Inspection Technology for Complex-Shaped Composite Components

针对航空航天异形截面复合材料构件的长距离无损检测难题,研究了一种基于超声特征结构导波的快速扫描技术。通过半解析有限元方法对具有各向异性、粘弹性的任意截面形状波导结构进行模态分析,在两种典型复杂复合材料构件单元,即翼梁弯角(R区)和加筋壁板粘接结构中定征出了能量高度汇聚的超声导波模式。该类导波被证明能够将声波能量高度聚集于特征结构内部,并引导所捕获能量仅沿其传播,且具有低色散、低衰减等优异的传播特性。进而,采用三维有限元仿真与实验测试方法,验证了所选导波模式的频散特性,并研究了其与特征结构内多种类型缺陷(如分层、裂纹、脱粘等)的声散射规律。利用声波–缺陷能量共振现象以及缺陷反射回波信息,实现了对长构件内部缺陷的精确定位。研究证明,所提出的超声特征结构导波检测技术可应用于飞行器复杂形状复合材料构件的远程、在役、快速检测。

Complex-shaped composite components have been extensively utilized in the aerospace industry.This paper investigates the feasibility of using ultrasonic feature guided waves(FGW)for rapid screening of two representative long-range composite structures,i.e.laminated bends and adhesive composite joints.Such FGWs are capable of focusing the propagation energy along the structural feature,with limited leakage into the adjacent plate.They also exhibit littledispersive and low-attenuative characteristics.Modal studies of the anisotropic viscoelastic waveguide were carried out via the semi-analytical finite element(SAFE)method to reveal the existing FGW modes.Both 3D finite element(FE)simulations and experiments were performed to cross-validate the modal properties of identified FGW modes and to study their interaction with different defects occurring in the structural feature,such as interlaminar delamination,cracks,and adhesive debonding.The wave-defect resonance phenomenon and the reflection behaviour were investigated for localizing these defects.The potential of proposed FGW-based approach for efficient damage detection in complex-shaped composite components is well demonstrated.