Transactions of the INDIAN CERAMIC SOCIETY Vol. 51 1992
Vapour Phase Synthesis of Ultrafine Non-oxide Powders
and their Sintering Behaviour*
AKio KATO
Pages : 6-16
DOI : 10.1080/0371750X.1992.10804523
Abstract
As technology advances, need for fine, homogeneous powders
has Increased. Among many new powder preparation techniques,
the vapour phase reaction method Is receiving Increasing
attention as the· preparation technique of powders of refractory
oxides and non-oxides. Powders produced by vapour phase
techniques can be characterized by high discreteness and
ultraflneness. In the present paper, the formation processes and
size control of particles of refractory nitrides and carbides by
vapour-phase reaction (CVD) method and their sintering behaviour
are discussed.
The formation processes of particles of the carbides and
nitrides can be divided into: (a) formation of adduct particles of
reactants and their thermal decomposition into carbide or nitride,
(b) formation of nuclei of carbide or nitride and their
growth, and (c) formation of metal particles and their nitridation
or carburization. The particle sizes which range from 0.01 to 0.5
jlm can be controlled by manipulating the reaction conditions.
Ultraflne CVD powders show high sinterabilities.
