MODELING THE EFFECTIVE DYNAMIC PROPERTIES OF FIBER COMPOSITES MODIFIED ACROSS LENGTH SCALES

摘要

In the present work, we aim to estimate the effective storage and loss moduli of bristled fiber composite material (modified composites), where the surfaces of fibers are radially grown or coated with nanostructures such as nanowires, nanorods, or carbon nanotubes (fuzzy fiber). We use the Eshelby integral formula, which plays a fundamental role in the micromechanics of composite materials and especially in gradient models of micromechanics that allow one to describe the scale effects. In a two-phase composite system, the use of an integral formula in the framework of a generalized self-consistent scheme allows accurate closed-form solutions of effective properties for the interphase layer and for the composite as a whole. We employ a variant of generalized Eshelby's homogenization method to deduce effective damping properties of multilayer nanostructured fiber composites where one layer is highly heterogeneous with respect to its mechanical response strain gradients. The novelty of the work lies in the fact of treating the ZnO nanowires and CNT "fuzzy" layers by the gradient model that consequently allows us to consider the extra gradient coefficient or internal length in relation to other constitutive and geometric parameters of the composite to definition of its overall mechanical and dynamical properties and functionality.