abstract
Yttrium- and ytterbium-stabilized alpha-SiAlON powders consisting of rod-like microcrystals were prepared by combustion synthesis. A quenching method was used to investigate the phase formation and microstructure evolution during the combustion synthesis of alpha-SiAlON. Three reaction stages were proposed for the formation of alpha-SiAlON as follows: nitridation of metal powders, formation of the co-existing liquid phase, and precipitation of alpha-SiAlON with the dissolution of nitrides. Different nucleation and growth modes of rod-like alpha-SiAlON crystals were observed: crystallization from liquid phase, or nucleation and growth based on the surface of as-existed large crystals. (c) 2005 Elsevier B.V. All rights reserved.
keywords
ALPHA'-SIALON CERAMICS; MECHANICAL-PROPERTIES; SEED CRYSTALS; MICROSTRUCTURE
subject category
Materials Science; Physics
authors
Liu, GH; Chen, KX; Zhou, HP; Pereira, C; Ferreira, JMF
our authors
