Investigation of ZnO Nanowire Interfaces for Multi-Scale Composites.

摘要

Over the past few decades composite materials have found use in almost every structural system due to their high specific strength, stiffness, and toughness with respect to other engineering materials. Composites also provide the ability to tailor the properties of the bulk material for an individual application. However, the ultimate success of a composite material is strongly influenced by the quality of the fiber-matrix interface. This research effort will seek to increase the performance of the fiber/matrix interface through the growth of nanomaterials on the reinforcing fiber ultimately to increase the material's strength, toughness, performance and safety. The goal of the current research program is to characterize advanced multi-scale composites fabricated through the growth of zinc oxide (ZnO) nanowires on the surface of the reinforcing fibers. The nanowires functionally grade the interface, improve bonding, and enhance load transfer between the fiber and matrix material leading to increased strength and toughness of the composite. This research program has sought to understand the mechanism responsible for increased strength such that the findings can be used to design other materials with unprecedented properties. Following an array of MD simulation and experimental testing we have been able to demonstrate that the surface oxygen content is directly related to the interface strength and that specifically the percent surface coverage of ketones (C=O) is directly related to the interface strength. This result has been demonstrated both through direct measurement on carbon fiber and through MD simulations.