Non-destructive Testing and Damage Assessment of Composite Aerospace Structures Using Lamb Waves

Kurzfassung

This paper shows the special requirements and challenges of non-destructive testing (NDT) methods that arise from the increasing use of composite materials in aerospace structures. Current NDT methods often fail due to the large size of the structures or the material properties of composites. Manual testing methods are very time consuming for large structures and therefore increase the grounding time of the aircraft. They are also subject to human errors and do not provide the documentation quality of automated systems. To solve these problems a method based on the propagation of Lamb waves is presented that can be used for testing and monitoring the structure for defects. An optical measurement platform for the detection of Lamb waves, that is currently being developed at the DLR, is presented and it is shown, how damages can be localized in complex parts. Based on wave propagation simulation and damage assessment techniques the speci?c impact of the damage on the integrity of the structure and suitable repair concepts can be derived.