Self-Healing of SiC-Al2O3-B4C Ceramic Composites at Low Temperatures

Self-healing ceramics have been researched at high temperatures, but few have been considered at lower temperatures. In this study, SiC-Al2O3-B4C ceramic composite was compacted by spark plasma sintering (SPS). A Vickers indentation was introduced, and the cracks were healed between 600 degrees C and 800 degrees C in air. Cracks could be healed completely in air above 700 degrees C. The ceramic composite had the best healing performance at 700 degrees C for 30 min, recovering flexural strength of up to 94.2% of the original. Good crack-healing ability would make this composite highly useful as it could heal defects and flaws autonomously in practical applications. The healing mechanism was also proposed to be the result of the oxidation of B4C.

Automated summary

In this study, a self-healing ceramic composite was prepared using spark plasma sintering at lower temperatures, and it was found that cracks could be completely healed in air above 700 degrees C.