Elastoplastic Behavior of Unidirectional Hybrid Composites Containing SiO_2 Nanoparticles Under Transverse Tension

摘要

This paper investigates the overall elastoplastic behavior of unidirectional fiber-reinforced polymer composites containing silica (SiO2) nanoparticles under tensile transverse uniaxial loading using a multi-procedure micromechanics-based ensemble volume-averaged method. In the first step, the elastoplastic behavior of a nanocomposite consisting of SiO2 nanoparticles embedded in a polymer matrix is modeled. The formation of the interphase region between the nanoparticles and the polymer is taken into account in the simulation. In the second step, considering the nanocomposite as the matrix and fiber as the reinforcement, the elastoplastic behavior of nanoparticle-fiber-reinforced hybrid composites is obtained. The effects of volume fraction and size of nanoparticles, interphase characteristics and fiber volume fraction on the elastoplastic stress-strain curves are examined. The results clearly highlight the benefits of SiO2 nanoparticles into the fibrous composites from a structural point of view. The elastic modulus and strength of fibrous composites can be significantly enhanced with adding nanoparticles. It is found that the interphase region plays a crucial role in the overall mechanical behavior of the hybrid composites. Moreover, the mechanical properties of hybrid composites are highly improved by decreasing the nanoparticle diameter. Finally, the elastoplastic behavior of nanoparticle-fiber-reinforced hybrid composites under transverse/transverse biaxial tension is provided. Comparisons between the predictions and existing experimental data are conducted to verify the predictive capability of the proposed approach.