Bio-inspired crack self-healing of SiC/spinel nanocomposite

Crack self-healing behavior of SiC/spinel nanocomposite, obtained from talc, aluminum and graphite powders was evaluated as a function of time, temperature and the environment atmosphere. The mechanism that was involved in the crack-healing was investigated and the outcome revealed both physical and chemical phenomena are involved in the healing process. In the presence of oxygen at high temperatures, SiC reacts with oxygen to form SiO2 which is accompanied with about 80% volume expansion. On the other hand, the formed silica reacts with the matrix and produces some transition compounds which can rebond crack walls together. The results showed that cracks can be completely healed after heat treatment at 1545 °C in static air for only 1 min.