ABSTRACT
The strength and reliability of brittle materials are controlled by the stress intensity factors associated with defects in the body and the resistance of the material to crack growth. The mechanisms (particle rearrangement, neck formation, densification, grain growth, etc.) which occur while sintering a green ceramic body affect both the evolution of the largest flaw and the fracture resistance, which depends on the average microstructure. Thus, in order to gain a full understanding of how processing parameters influence the strength of ceramics it is critical to combine the evolution of the extreme microstructural features (flaws) with average microstructural features.
In this study, we report on the evolution of elastic modulus, crack tip toughness and strength as a function of density. In addition, we have also studied the evolution of the size of artificially induced strength limiting flaws. Knowing the fracture toughness, strength and size of the flaw, the shape factor has been estimated as a function of density.
