Reaction of Zircaloy-4 with tellurium under different potentials

Corrosion behavior of Zircaloy-4 has been studied under different oxygen potentials and tellurium vapor pressures. The oxygen potential was controlled by buffer and its range was ∼600 kJ/mol to ∼430 kJ/mol. Under the condition of oxygen potential of less than ∼500 kJ/mol with tellurium vapor, the double corrosion layers were observed on the surface of Zircaloy-4 specimens, which consist of zirconium telluride and zirconium oxide. And thickness of corrosion layer was increasing with tellurium vapor pressure. Above the oxygen potential of ∼430 kJ/mol, only zirconium oxide was observed regardless of coexistence with tellurium vapor