E. V. Nikitina, E. A. Karfidov, N. A. Kazakovtseva.
ABSTRACT
The article discusses the degradation of ceramic materials based on magnesium oxide, aluminum oxide, and silicon nitride in the LiCl – KCl melt, with the addition of uranium, cerium, and neodymium trichlorides of various concentrations in the temperature range 470–650°С. Gravimetric, chemical-analytical, x-ray spectral and x-ray phase analysis methods were used. It was established that all the studied ceramic materials are chemically resistant in these melts. An important role in the choice of material for structural elements is played by the porosity of ceramics. The larger it is, the greater the increase in mass after the experiment, which increases with increasing temperature. Magnesium oxide-based ceramics react with alumina to form magnesium aluminate, which prevents them from being used together. The best results were shown by ceramic based on silicon nitride, as it is low porous and chemically stable. The cerium and neodymium trichloride additives introduced into the melt do not significantly affect the studied ceramics.
KEY WORDS:
magnesium oxide, aluminum oxide, ceramic degradation, silicon nitride
DOI: 10.31857/S0235010620050096