A novel model to simulate the formation and healing of cracks in self-healing cross-ply composites under flexural loading. (1st March 2020)

• Record Type: Journal Article
• Authors: Shabani, P.; Shokrieh, M.M.; Saeedi, A.
• Is Part Of: Composite structures. Volume 235(2020)
• Publication Date: 2020-03-01
• Subjects: Matrix cracking -- Self-healing -- Diels–Alder reaction -- Conversion degree -- Multiple healing; Composite construction -- Periodicals; Composites -- Périodiques; 624.18
• DOI: 10.1016/j.compstruct.2019.111750
• Languages: English
• ISSNs: 0263-8223

Abstract

Abstract: The formation and healing of cracks in fiber-reinforced composites made of a thermally remendable polymeric matrix were studied. A new thermally remendable polymer, using furan and maleimide moieties based on the Diels–Alder reaction was synthesized and employed for the fabrication of fiber-reinforced composites. To find the healing efficiency of composites, three-point bending specimens with the stacking sequence of [903 /0/903 ] were prepared. The specimens were initially subjected to tensile loading until reaching the characteristic damage state. Then, the flexural modulus and strength after the healing up to different conversion degrees were obtained and compared with the virgin specimens. The results revealed over 95% recovery of the flexural strength and modulus after the complete healing. In addition, the effect of multiple healing on the healing efficiency was investigated and it was observed that the percentage of recovery would remain constant in the absence of fiber breakage. Using the shear-lag analysis and the classical lamination theory, a novel model was developed to simulate the residual flexural modulus of the damaged specimens as a function of the crack density. Moreover, the proposed model was extended to predict the recovered flexural stiffness after the healing of the specimens. A comparison of the results of the model and experiments validated the capability of the proposed model.