Ceramic bodies of increases breaking strength - consisting of two different zirconia and alumina phases

摘要

Ceramic body consists of a matrix and >=1 dispersed ceramic phase of increased ultimate extension. Both the matrix and disperse phase consist of alumina and unstabilised ZrO2 particles, the dispersed phase contg. 3 vol.% more ZrO2 than the matrix. Pref the matrix contains 9-17 vol.% and the disperse phase 12-20 vol.% ZrO2. The body is used for ductile high temp. gas turbine elements. The disperse phase exists in different enantiotropic solid modifications at room temp. and at the firing temp. Due to the differences in density of the 2 forms there is a high concn. of very fine microcracks throughout the body. The fracture energy of the composite body is much greater than that of either of the component materials.