Built-in piezoelectrics for processing and health monitoring of composite structures

This paper presents on-going research for developing advanced composite structures with built-in piezoelectrics which will be capable of self-monitoring of the manufacturing process and self-diagnosing of service-induced damage. For manufacturing monitoring, diagnostic waves generated by a built-in piezoactuator were monitored by a nearby built-in piezo-electric during a cure. Experiments have demonstrated that the changes in the diagnostic waves monitored during a cure could be utilized to evaluate the quality of the finished components. For in-service damage detection, the current work was focused on diagnosing service-induced impact damage. Based on distributed piezo-sensor measurements, a model and a computer code, IDIMPACT, were developed which can estimate both the impact force and location in a composite plate. It is shown that impact damage in composites can be detected by selecting appropriate Lamb waves generated from built-in piezoceramics. (Author)