Interaction of sintered aluminum nitride with the KF-AlF3 melt at 700–800°C

Interaction kinetics of the aluminum nitride-based sintered composite material with the potassium cryolite melt with the cryolite ratio KO = 1.3 at 700–800°C is investigated by the continuous weighing method. It is established that the composite is almost unaffected by the melt at t = 700°C. The corrosion rate increases as the temperature increases. The material interacts with the molten salt through its oxidation stage by oxygen dissolved in the melt. This is also accompanied by the dissolution of oxygen-containing impurities that are initially present in the material. No interaction of sintered aluminum nitride with the melt under study was observed in the absence of the oxidant and with the concentration of alumina dissolved in cryolite close to saturation.