Nondestructive evaluation and 3-D imaging of impact damage in CFRP/Ti fibre-metal laminates using synchrotron radiation laminography

Nakatani, Hayato*; Kajiwara, Kentaro*; Akita, Koichi; Ogihara, Shinji*

Fibre-Metal Laminates (FMLs) are hybrid materials that consist of thin layers of metal and fibre-reinforced polymer, and have already been applied several aircraft. It is well-known that there is a difficulty in non-destructive assessment of damage in FMLs using laboratory radiography or X-ray computed tomography since FMLs have laminate structure of materials with different X-ray absorption coefficient. Synchrotron radiation laminography at SPring-8 in Japan is employed to assess low velocity impact damage in CFRP/Ti laminates as FMLs. It is verified that how each damage mode, such as crack in titanium layer, fibre break, matrix cracking, interlaminar delamination in CFRP layers and interfacial debonding between CFRP and titanium layers, can be observed in obtained reconstructed slice images. Three-dimensional imaging of the low velocity impact damage is also demonstrated by stacking the reconstructed slice images, and that is to our knowledge a novel result.