SiAlON ceramics from nanopowders

✍ Scribed by Ilmars Zalite; Natalja Zilinska; Gottfried Kladler

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 830 KB
• Volume: 28
• Category: Article
• ISSN: 0955-2219
• DOI: 10.1016/j.jeurceramsoc.2007.09.020

✦ Synopsis

Different compositions of ␣and ␣-/␤-SiAlON materials have been prepared from two different starting powders (commercial and nanopowder). Separate nanopowders and their composites were used as nanocomponents: Si

produced by the method of plasma-chemical synthesis. Powder mixtures of the same composition from ␣-Si 3 N 4 powder (Ube grade SN-E10) and additives (Y 2 O 3 , Al 2 O 3 and AlN) produced by a conventional powder mixture process were used for comparing. Compositions have been pressure less sintered under nitrogen atmosphere until 1650 • C with a heating rate of 10 • C/min and holding time of 2 h. The densification behavior of the materials depends on the powder composition and the size of the particles used for starting powder. It is possible to obtain dense materials from nano-sized powder at relatively low temperatures (1500-1600 • C) with good mechanical room temperature properties in comparison with material made of a m-sized starting powder.