Observation of Interfaces of Si-Ti-C-O Fiber/Mullite Matrix Composites by Analytical Transmission Electron Microscopy

Abstract

The interfaces of Si-Ti-C-O fiber/mullite matrix composite hot-pressed at 1500°C in N₂ atmosphere were characterized by analytical transmission electron microscopy. Partial decomposition of Si-Ti-C-O fibers produced graphite layers 30-60 nm thick on the surface of fibers and crystalline Ti-C-N particles of about 800 nm in size at the triple points among fibers. Diffusion of Al and O from mullite matrix into Si-Ti-C-O fibers was interpreted as being due to the reaction between mullite and C or SiC segregated on the surface of fibers.