REFRACTORY CERAMIC HAVING A HIGH SOLIDUS TEMPERATURE, ITS MANUFACTURING PROCESS AND STRUCTURAL PART INCORPORATING SAID CERAMIC

摘要

The refractory ceramic composite material useful in a piece of structure, comprises hafnium dioxide grains (37-61 vol.%) of monoclinic structure (1), hafnium dioxide grains (10 vol.%) of cubic structure (2) stabilized by yttrium oxide (1 mol%), closed pores (3) having average size of 3 mu m, and 0.5 vol.% of open pores (5), which are not inter-connected. The cubic structure forms inclusions (4) in the monoclinic structure. The grains of cubic structure are allocated in a homogeneous manner in the whole volume of the ceramic material. An independent claim is included for a process for fabricating refractory ceramic composite material by powder metallurgy.