Detection and Characterization of Defect in Carbon Fiber Reinforced Composite Laminate Using Passive Thermography

Abstract

Real-time non-destructive assessment is important during load testing of composites. Overlay for rising use of Carbon Fiber Reinforced Polymer (CFRP), the fast, visible, and free of Interference technique for discovering mechanical influence deterioration is critical requirement. The main concept of the research experiment using passive thermographyis to locate the damaged areas during polymer deformation using the energy release. The test specimens were establishedover the temporaland spatial temperature distribution. Based on that, the forms of CFRP impact damage are described.The purpose of this paper is to use thermography and Ultrasonic to classify the types of impact damages.The results obtained show that under the different impact energies various types of impact damage occur and can be defined in the thermographic picture. Based on the fiber composite material used CFRP, Material thickness and impact energy a measure of sensitivity of the detection of these methods for the different damages is performed in this paper.  The methods of thermography analysis used after the damage are complemented by high-temporal resolution thermography measurements, which are documented during the effect. The investigations of the impact damaged CFRP test specimens with thermographyshow that kind and shape of the damage. In the test specimens, a defined large crack can be detected which has spread parallel to the course of the fibers of the layer of the laminate. To this end, various specimens undergo impact testing with different energies of five, ten, fifteen, twenty, thirty, and thirty six Jouleand monitored by infrared camera. Informationhandlingprocedures areobtainablewhichfacilitaterecognition of the minorchangesthermo-graphicwaveformsresultantbydefectdevelopment in actualphase. The findings of the passive thermography measurements are compared with the validation ultrasonic measurements.