Multimodal optical non-destructive evaluation of impact damage in composite materials

Structural integrity of composite materials is vital for aerospace applications, requiring advanced non-destructive inspection (NDI). This study combines shearography and digital image correlation (DIC) to assess carbon-fiber reinforced polymer (CFRP) samples after the impact. Impact testing via a drop tower induced different damage types, detected by both techniques. Four-point bending test enhanced defect visibility. The measurements were performed by shearography and 3D DIC using the same cameras from the 3D shearography system. Shearography identified defects earlier than DIC, while DIC offered bigger range of displacements and strain measurements highlighting the complementary role of both methods and multimodal NDI test’s effectiveness in detecting impact damage and manufacturing defects.