Quasi static mechanical study of vacuum bag infused bouligand inspired composites

• Published in: Polymer testing Vol. 100; p. 107261
• Main Authors: Amorim, L., Santos, A., Nunes, J.P., Dias, G., Viana, J.C.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-08-2021; Elsevier
• Subjects: Bouligand architecture; Carbon fibre; Failure mode; FE modelling; Quasi-static testing; Vacuum bag infusion; Bouligand architecture; Failure mode; Carbon fibre; Quasi-static testing; Vacuum bag infusion; FE modelling
• ISSN: 0142-9418; 1873-2348
• DOI: 10.1016/j.polymertesting.2021.107261

Three novel Bouligand inspired composites were produced by vacuum bag infusion manufacturing process and their quasi-static mechanical performance were compared to a conventional aircraft laminate. A morphologic/physical study was first conducted for all configurations and their mechanical response under tensile, three-point bending (3-PB) and interlaminar shear strength (ILSS) tests were then evaluated and discussed. No significant number of voids were detected into laminates, however, a rough and poor defined interlaminar region was observed in both Bouligand-like configurations. Under quasi-static mechanical solicitations, and when compared to reference layup, bioinspired configurations have shown similar and 18% higher tensile and flexural modulus. However, the progressive and translaminar failure mode, typically observed in these configurations, led to a lower load bearing capability. Despite presented similar interlaminar resistance than reference, finite element models built have revealed a good correlation between cross-section stress field and failure mode observed experimentally.
•Vacuum bag infused carbon/epoxy bioinspired Bouligand-like laminates.•Morphological analyses of vacuum bagged composites revealed a rough and poor-defined interlaminar region.•Bouligand-like layups have delayed catastrophic failure by the formation of a progressive and translaminar matrix cracking.•Finite element (FE) models revealed a good correlation between stress fields and failure mode observed experimentally.