Koroze konstrukčních materiálů působením kyseliny borité

A contact between the primary medium containing boric acid and construction metallic materials cannot be avoided in production conditions of the primary circuit of nuclear power plants. The goal of this experimental project was to simulate selected exposures of construction materials to the primary medium and quantify its corrosion impacts. The basic factors affecting corrosion include the temperature of the material surface, acid concentration and the possibility of steam suction from the surface. The steam layer forms at a high temperature and protects the surface from the contact with boric acid and prevents corrosion. Evaporation of boric acid also depends on the quantity of water (boric acid concentration). The excess of water enables distillation of boric acid and the excess of boric acid results in formation of a harmless glasslike layer from the boric acid melt.