A new methodology to guarantee the structural integrity of ceramics component using self- crack - healing ability

摘要

A new methodology to guarantee the structural integrity of ceramics component has been proposed. This methodology consists of following three stages ; (a) Crack-healing at the best conditions, (b) Proof test and (c) In-situ crack-healing. Above (a) is suitable to heal the surface cracks those were introduced by machining. Above (b) is necessary, because embedded flaws such as cracks and pores can not be healed at the present stage. For the flaw-healing, oxygen is necessary. If, crack initiated during service, structural integrity maybe reduced considerably depending on crack size. However, if material has in-situ crack-healing ability and heal the crack during service, it would be desirable for the high structural integrity. Using the past studies related to crack-healing, bending and fatigue strength of crack-healed member at elevated temperature, in-situ crack-healing behavior and proof test theory, usefulness of this new concept has been explained concretely.