Self-healing ceramics can heal cracks autonomously like human bones, and since they were discovered by a research group at Yokohama National University in 1995, they have been used worldwide as next-generation heat-resistant materials for aircraft engine turbines. It has been attracting attention.However, the detailed mechanism of healing has not been elucidated, and in addition, there is a problem that cracks can be completely healed in a short time only in a limited temperature range of 1200 to 1300 ° C. The development of various ceramics has been desired.

　This research group investigated the healing mechanism of ceramics, and the healing of self-healing ceramics is the mother body of ceramics, in which oxygen invaded from cracks reacts with silicon carbide contained in ceramics to synthesize silicon dioxide (inflammation). It was revealed that alumina and silicon dioxide react to fill cracks (repair) and crystallize to restore strength (modification), which is a three-step process similar to bone healing.

　Furthermore, by arranging manganese oxide that activates the healing of ceramics at the boundary of crystals, using the body fluid network that promotes bone healing as a hint, the healing time of cracks, which used to take 1000 hours at 1000 ° C with conventional materials, can be reduced. Succeeded in shortening to the fastest 1 minute.
　Based on this result, the research group will select the type of healing active phase appropriately and develop innovative high-temperature ceramics with excellent self-healing function that "does not break even if cracked". It is said that we will aim.

Paper information:[Scientific Reports] A Novel Design Approach for Self-Crack-Healing Structural Ceramics with 3D Networks of Healing Activator