Abstract
Damage-mechanics concepts are incorporated into a fracture-mechanics interpretation of multiple grain-boundary cracking in uniaxial tensile creep specimens that undergo power–law creep deformation. Initially, methods of evaluating the fracture–mechanics creep parameter C* for a structure containing a single macroscopic crack are extended to a uniform distribution of grain-boundary voids. Damage-mechanics models are then applied to describe damage accumulation. It is shown that, when the voids grow as disc-shaped cavities, the analysis yields predictions of growth rates which are consistent with characterizations of macroscopic crack growth behaviour involving the exhaustion of the available creep ductility in a process zone at the crack tip.
MST/195
Get full access to this article
View all access options for this article.
