This study was carried out to evaluate the repeated crack-healing properties of SiC composite ceramics and to investigate and analyze the Vickers hardness and fracture toughness. SiC composite ceramics were able to heal repeated cracks, but this crack-healing was only suitable up to two times. The oxygen of the three-times crack-healed specimens increased 1158% over that of the as-received specimen. The surface oxide was found to be SiO₂, Y₂Si₂O₇, and Al₅Y₃O₁₂. The Vickers hardness and fracture toughness decreased as the number of crack-healings increased, and the dispersion was increased as well. The Vickers hardness and fracture toughness were analyzed using the two-parameter Weibull statistics. It was concluded that the Weibull distribution can properly describe the Vickers hardness and the fracture toughness of SiC composite ceramics. Ceramic structures that can be repeatedly crack-healed can save costs due to reduced manufacturing costs, replacement costs, shutdowns, etc., which will ensure enormous economic efficiency.

Keywords: SiC ceramics, Repeated crack-healing, Statistical analysis, Vickers hardness, Fracture toughness, Economics