Carbon Fiber Nanotube Reinforced Alumina Nanocomposite

Reinforced tough ceramics that fail gracefully are requied for structural components in airframes and engines of military and commercial airplanes. The expected toughening was not realized when alumina powder, containing carbon nanotubes (CNTs), was consolidated by hot isostatic pressing due to the destruction of the CNTs at the high temperatures encountered. HY-Tech has demonstrated in the Phase I effort that microwave sintering can be used to consolidate alumina/CNT mixtures without destroying the CNTs. HY-Tech proposes to study the relationship between the preparation and consolidation processes with the resulting microstructure and mechanical properties of the nanocomposite material in the Phase II effort. The volume fraction of CNTs, their quality (single walled or multi-walled), and their surface conditions will be varied as widely as possible along with the starting particle size, microwave heating rate and sintering conditions. The mechanical properties will be correlated with the microstructure achieved by University of Missouri/ Rolla investigators to determine the dominant material reinforcement process at play.