THE PRODUCTION OUTLINE OF MICROPOROUS AND DENSE CERAMICS

摘要

The corrosion resistance of refractory materials depends on the number and size of open pores. Aggressive liquid media easily infiltrates pores of diameter bigger 5 - 10 micrometers. Refractory that does not have such big pores will thus be to some extent resistant to corrosion. The outline for the production of non-porous or micro-porous refractory materials is based on e new unique technology of vacuum granulation of ceramic powder slurries. Due to such a granulation where the grain are of a few micrometers, it is possible to obtain die stamping/compacts of apparent density equal 85% of theoretical density. Pressing the typical powder granulated products allows obtaining die-stamping density (including isostatic die stampings) of not more than 55 - 65% of theoretical density. Such a high degree of powder material concentration - not possible with other methods -gives very good economical and technological results during burning process. Fine powders sinter very intensively, the burning time can be shortened and sintering process can be carried out in lower temperature.