Carbon Fiber Nanotube Reinforced Alumina Nanocomposite

Nanocomposites of carbon nanotubes (CNTs) dispersed in alumina powders and consolidated to near 100% theoretical density at low temperatures have been shown to have a four point bend strength 3 times that of pure alumina ceramics. Recently, in situ synthesized CNTs have been produced in alumina powders containing finely dispersed Fe nanoparticles. The anticipated improvement in mechanical properties had not been realized from the collagen like scaffolding of the CNTs when the nanocomposites were consolidated using hot isostatic pressing (HIP). This disappointing performance was attributed to the destruction of the CNTs by the high temperatures used in the HIPing. HY-Tech proposes to consolidate alumina nanocomposite green bodies containing in situ synthesized CNTs using a low temperature pressureless sintering approach. The characteristics of the CNTs and microstructure of the composite will be measured at different times in the fabrication process by scientists at the University of Missouri-Rolla. The studies will assess the effects of varying fabrication parameters on survivability of the CNTs and the bend strength of the nanocomposite material.