N. Dey et al., MODELING STATIC AND CYCLIC FATIGUE IN CERAMICS CONTAINING A VISCOUS GRAIN-BOUNDARY PHASE, Acta metallurgica et materialia, 43(6), 1995, pp. 2163-2175
Citations number
31
Categorie Soggetti
Material Science","Metallurgy & Metallurigical Engineering
In ceramic materials at elevated temperatures failure is often the res
ult of the propagation of a single dominant crack when the stress is s
ufficiently high. The surface behind the crack tip is extensively brid
ged by adhesive viscous ligaments and extent of crack tip shielding by
these viscous ligaments depends on the microstructure, strain rate an
d temperature. A mechanistic model has been developed that takes into
account the effects of grain size, width and viscosity of the viscous
grain boundary layer and strain rate to predict the ratio of static to
cyclic loading lifetime. A single dimensionless scalar parameter has
been identified as a critical parameter to determine whether cyclic lo
ading will be equally damaging or less damaging than the corresponding
static loading agree with experimental results of various authors.