ChemInform Abstract: In situ Reacted Rare-Earth Hexaaluminate Interphases.

✍ Scribed by M. G. CAIN; R. L. CAIN; M. H. LEWIS; J. GENT

• Book ID: 101850186
• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 29 KB
• Volume: 28
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199742014

✦ Synopsis

In situ Reacted Rare-Earth Hexaaluminate Interphases. -Oriented hexaaluminate layers are formed by in situ reaction between a Ce-doped ZrO2 interface coating on sapphire fibers and an outer α -Al2O3 coating by heating in reducing environments. The reduction of Ce4+ and Zr4+ ions to their three-valent states results in a destabilization phenomenon. Diffusion of Ce3+ from solid solution with zirconia stabilizes the layered hexaaluminate through solid solution reaction with alumina. The preferred growth of the hexaaluminate parallel to the coating interface is the required orientation for enhanced debonding at the fiber/mixture interface in long-fiber-reinforced ceramic mixture composites. -(CAIN, M. G.;