Over recent years, it has been established that rite incorporation of metal
lic particles into a ceramic matrix can lead to enhanced fracture propertie
s. Relatively few attempts, however, have been made to establish whether or
Mot the improved fracture toughness typically observed in such composite s
ystems can offer improved performance in demanding environments. The curren
t study, is concerned with the thermal shock behaviour of a ceramic matrix
composite consisting of an alumina matrix containing 20 vol% of discrete ir
on particles. The composite material has been produced by both hot pressing
and conventional sintering techniques. The hot pressed composite shows a g
reater resistance to thermal shock than the monolithic matrix, both in term
s of the critical temperature differential and retained strength, whereas t
he sintered material has been found to behave as a typical low strength ref
ractory ceramic. The calculation of thermal shock resistance parameters for
the composites and the monolith has indicated possible explanations for th
e differences in thermal shock behaviour. (C) 1999 Elsevier Science Limited
. All rights reserved.