PURPOSE: To estimate the life of a ceramic member in a short time by means of a simple nondestructive inspection by measuring the growth of ceramic particles for the ceramic member or by measuring the physical quanitye, of a member, which is changed by the diffusion of an external element to a ceramic.
CONSTITUTION: As a base material in a case in which a ceramic is used as a sprayed coating, an Ni-based alloy 4 is used, its surface is degreased and cleaned, and a CoNiCrAlY alloy 3 as a coupling layer whose corrosion resistance is excellent is coated by a plasma spraying operation. A ZrO2 coating layer 1 is formed on its surface, a heat treatment is executed in a vacuum, and the diffusion treatment of the coupling layer and the base material is executed. A sample which has been obtained is held at, e.g. 1500°C for many hours, and the relationship between a particle growth operation and its time is found. Then, particles are grown with the passage of the heating time, pores 2 are reduced, and a particle size corresponds to the holding time. Consequently, when the relationship between a physical quantity corresponding to a heat history and the life of a ceramic member is found in advance, the life of the ceramic member can be estimated by its physical quantity.
YASUTOMI YOSHIYUKI
MIYATA MOTOYUKI
TAMAOKI HIDEKI
WADA KATSUO
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