Dynamic fragmentation of ceramics under tension and compression

Grain-level cohesive finite element analysis of dynamic fragmentation under rapid compression. This figure illustrates the effect of the lateral confining pressure p ranging from 0 GPa (left) to 1 GPa (right) and shows how an increasing confining pressure limits the amount of observed damage, which increasingly takes place in a localized shear-like fashion.

Effect of the confining pressure p on the macroscopic stress-strain curve under rapid compression for a friction coefficient of 0.4. In the absence ofconfining pressure (red curve), the response is brittle, while, under high confining pressure (black curve), the ceramic material shows a substantial amount of apparent ductility due to the frictional interaction between the fragments.

Effect of the confining pressure p and friction coefficient mu on the type of observed damage in an almina specimen subjected to dynamic compression, showing shear-dominated failure under high confining pressure (left figures) and axial splitting failure in the absence of confining pressure (right figures). Damage is illustrated for two values of the damage index (DI), which quantifies the amount of distributed damage.