Composite aircraft joint experimental testing with digital image correlation

Abstract

The main goal was to establish results of the individual joint strength characteristics used in composite laminate structure, in order to be used for design computations in airframe structures. A carbon-epoxy composite specimen includes a brass sleeve that is used to connect other metal parts by a bolt, used on light-weight category aircrafts. 11 specimens were tested and pulled by a tensile test machine. The tension mechanisms associated with failure modes of bolted joints in advanced composites is explained. The work is based on experimental test observations, performed by Instron 8516 servo-hydraulic testing machine and analyzed further by Digital Image Correlation (DIC) technique to define failure load of this metal-composite interconnection. Comparison of DIC results is made in parallel with test recorded data as verification. Conclusions include a failure analysis and observations learned during the experiment.