Influence of water chemistry on the corrosion mechanism of a zirconium–niobium alloy in simulated light water reactor coolant conditions

• DOI: 10.1016/j.corsci.2009.08.045
• Publication Date: 2009-08-24T08:08:35Z
• Authors: Martin Bojinov; Vasil Karastoyanov; Petri Kinnunen; Timo Saario
• Keywords: 0103 physical sciences; 02 engineering and technology; 0210 nano-technology; 7. Clean energy; 01 natural sciences

The oxidation of the zirconium alloy E110 inf simulated nuclear power plant coolant at 310 °C is characterised using in situ Electrochemical Impedance Spectroscopy (EIS) and ex-situ microscopic observations. EIS data have been fitted to a transfer function derived from the Mixed Conduction Model. The kinetic parameters characterising the oxidation process – interfacial rate constant of oxidation, diffusion coefficient of oxygen vacancies, and field strength in the inner layer – have been estimated. The dependence of their values on LiOH/KOH/NaF content are discussed in terms of an enhanced rate of dissolution of the barrier layer at higher level of alkali and fluoride.