Engineering of Ceramic Nanocomposites

The aim of the project is to develop nanostructured ceramic composites based on either Al₂O₃ or other ceramic components, such as mullite, through novel powder processing and fabrication techniques, including in-situ reactions during fabrication, and to obtain an improved understanding of the development and stability of ceramic nanostructures and their mechanical properties. The nanocomposites will be formed either by processing of nanosized starting powders or from ordered mixtures where collodial sol particles or alkoxides are used as precursors to the additives. These species are either absorbed on or reacted with the surface of the ceramic powder which makes it possible to retain a homogeneuos mixture during powder preparation and forming. SiC, ZrO₂ and metal particles will be used as toughening and strengthening agents, and mechanical and transport properties will be realated to the fine scale structure and local chemistry of the ceramic nanocomposite. The fine scale structures will be characterized by high resolution ananlytical electron microscopy and relationships between nanostructure, fabrication process and physical and chemical properties will be established.