| Abstract Scope |
Crystallographic anisotropy plays a critical role in controlling the propagation path of cracks in ceramics. This talk will present a multiscale mechanistic understanding of crack-path evolution in SiC/SiC composites as a function of inclusion size, inclusion shape, inclusion orientation, crack length, porosity size, and crack-pore interaction distance. We will show that -- depending on the degree of anisotropy and geometric parameters, a propagating crack can get deflected at the inclusion interface or penetrate through the inclusion. Also, a propagating crack around a pore exhibits three distinctive situations: crack bifurcates and never interacts with the pore, bifurcated crack interacts with the pore and gets terminated, the crack propagates along the symmetry plane and annihilated at the pore, and continued growth of the terminated crack at the pore requires renucleation. We will discuss the challenges in modeling the deflection vs. penetration mechanisms in ceramic-ceramic composites at atomistic and continuum scales. |