Corrosion of Alumina Ceramics in an Aqueous Solution of Sodium Chloride

Abstract

Two alumina based ceramics with 99.99 % and 95 % of Al2O3 were evaluated after dissolution in an aqueous solution containing 0.5 mol/l NaCl at temperatures of 150 and 200 °C. The weight loss of liquid phase sintered alumina was mainly attributed to congruent dissolution of SiO2 and CaO from grain-boundary amorphous film, which is accelerated at higher temperature, accompanied by precipitation of silicaceous phases from oversaturated solution at 200 °C. Pure polycrystalline alumina corroded by loss of alumina g…