Issue 61

C. Bellini et alii, Frattura ed Integrità Strutturale, 61 (2022) 410-418; DOI: 10.3221/IGF-ESIS.61.27

a b Figure 5: SEM micrographs of the long beam specimens with structural adhesive: a) top section, b) bottom section.

a b Figure 6: LOM micrographs of the long beam specimens with structural adhesive: a) top section, b) bottom section.

a b Figure 7: LOM micrographs of the short beam specimens with structural adhesive: a) top section, b) bottom section. Long beam specimens without adhesive bonding had fracture characteristics that were similar to those found in specimens joined with adhesive. The SEM study revealed the longitudinal fibres failure mode, which was tensile failure in the bottom section and crushing in the higher one, as well as the existence of cracks in the crosswise bundles. Furthermore, the crack did not grow through the CFRP plies into the metal sheet in this situation. Even though some sections of the reinforcement bundles stayed stuck to the metal, the composite was completely separated from the metal, as visible in Fig. 9a. The LOM

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