A new in situ peeling test for the characterisation of composite bonded joints

At the moment, bonded joints quality on composites used in aeronautical industry is verified based on the determination of the interlaminar fracture toughness (Gc) obtained by means of the Double Cantilever Beam (DCB) or the Climbing Drum Peel (CDP) tests. Although they are well-established tests, they have known limitations. This investigation presents the design and validation of a new device that carries out a peeling test, its main advantage being the capability to perform the test in situ, i.e. directly on the actual aircraft production line without the necessity to extract coupons for a laboratory test. An experimental campaign has been carried out, the obtained results being comparable to those obtained with the traditional DCB and CDP procedures. Numerical studies have allowed to understand the delamination mechanisms presented at the different tests, confirming that experimental Gc evaluation obtained is adequate.