Influence of the anisotropy of sisal fibers on the mechanical properties of high performance unidirectional biocomposite lamina and micromechanical models

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2021-04, Vol.143, p.106320, Article 106320
• Main Authors: Zuccarello, Bernardo, Militello, Carmelo, Bongiorno, Francesco
• Format: Article
• Language: English
• Subjects: A. Biocomposite; A. Natural fibers; B. Anisotropy; C. Micro-mechanics
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2021.106320

•Anisotropy of the sisal, also in term of mechanical strength, has been highlighted.•Observed splitting phenomena affects the main mechanical properties of the lamina.•SEM analyses corroborate that splitting affects also shear and compressive strength.•The experimental results have allowed to implement reliable micromechanical models.•The main mechanical parameters useful at the biocomposite design stage, are given. High performance biocomposites reinforced by sisal fibers, are between the most promising materials that could be used in various fields, from automotive to civil constructions, thanks to their good mechanical performance, as well as to the low cost and the great availability of the fiber. Nevertheless, at present their practical use is prevented by the limited knowledge of their mechanical performance. The results of the present study have shown that the intimate fibrillar structure of the sisal fiber is associated with a high anisotropy involving not only the elastic parameters, but also the damage processes with typical fiber splitting phenomena, that influence noticeably the biocomposite strength under transversal tensile/compressive, longitudinal compressive and shear loading. Also, they have permitted to implement new micromechanical models that can be used at the design stage, in all practical structural applications where low cost green biocomposites reinforced by sisal long fiber could be advantageously used.