We study thermal crack shielding and thermal shock damage in a double-edge
cracked metal-particle-reinforced ceramic matrix composite subjected to sud
den cooling at the cracked surfaces. Under severe thermal shocks, the crack
will grow but will be bridged by the plastically stretched metal particles
. A linear softening bridging law is used to describe the metal particle br
idging behavior. An integral equation of the thermal crack problem incorpor
ating the bridging effect is derived and the thermal stress intensity facto
r at the bridged crack tip is calculated numerically. It is found that the
thermal stress intensity factor is significantly reduced by the metal parti
cle bridging. While the crack growth in thermally shocked monolithic cerami
cs is unstable, the composite can withstand sufficiently severe thermal sho
cks without failure. (C) 1998 Elsevier Science Ltd. All rights reserved.