Characterization of defects in curved CFRP samples using pulsed thermography and 3D Finite Element Simulation

Abstract

Active thermography is a technique for non-destructive testing used for a contact-free inspection of components and materials. Thermographic methods are considered as an alternative to the state of the art techniques of ultrasonic- or X-raytesting. In particular, composite materials like Carbon Fibres Reinforced Plastics (CFRP), are increasingly analyzed by means of Active Thermography in order to detect defects like voids, delaminations or inclusions of foreign materials. Although much progress has been achieved in these fields in the last years, the studies and applications of thermographic detection of flaws are restricted to specimens with simple geometries in most cases found in literature. For industrial applications, however, components with complex geometries are of even prior importance [1]. In complex structures the temperatures after thermal excitation are influenced not only by material and defect properties but also by geometry effects and details of the excitation conditions. Thus the evaluation procedures used in the case of simple geometries cannot be applied in complex structures