Guided-wave based damage detection method for various materials using piezoelectric sensors/actuators

In this study, the guided wave technique is applied to nondestructively assess the damage in various engineering materials, like alumina, laminated composites, and composite sandwiches. A combined theoretical, numerical and experimental investigation of the pulse-echo method using piezoelectric sensors and actuators is conducted. The dispersion effect of wave guides on these materials is first analyzed, and the transient propagation process of wave guides and its interaction with inside damages are then numerically simulated. The implementations of the pulse echo method are illustrated in experimental testing and damage detection of aluminum beams, carbon/epoxy laminated composite plates, and composite sandwich beams. In particular, the experimental results on damage detection of the composite sandwich beams are reported and discussed. As illustrated in this study, the pulse-echo method combined with piezoelectric material can be used effectively to locate damage in various engineering materials and structures.