\textbf{Asperities, Crack Front Waves and Crack Self Healing}

We have performed petascale simulations to study~nanomaterial systems capable of sensing and repairing damage in high temperature/high pressure operating conditions. The system we have studied is a~ceramic nanocomposite consisting of silicon carbide/silicon dioxide core/shell nanoparticles embedded in alumina. We observe that the interaction of the crack with core/shell asperities gives rise to crack-front waves. We also study crack healing by diffusion of silica into the crack as a function of nanoparticle size and inter-particle distance. Our results are well supported by experimental observations.