N. A. Kazakovtseva, M. V. Mazannikov, E. V. Nikitina, E. A. Karfidov, A. M. Potapov.
ABSTRACT
The corrosion-electrochemical behavior of molybdenum was studied depending on the composition of the melt (simulators of spent nuclear fuel (SNF) components) in an oxidizing atmosphere. A thermodynamic analysis of possible corrosion processes was performed in the HSC Chemistry 9.0 program in the Equilibrium calculations module. The method of gravimetry estimated the rate of corrosion of the metal. Using the methods of X-ray microspectral and X-ray phase analysis, the products of the corrosion process are compared real and expected based on thermodynamic calculations. By the atomic absorption method, the concentration of molybdenum in frozen samples of the melt was studied. The corrosion rate of molybdenum depends on the duration of the test. The decrease in the corrosion rate over time can be explained by the accumulation of Nd3+ and Ce3+ ions in the near-electrode layer; corrosion proceeds in the diffusion mode. The corrosive activity of the salt melt increases with increasing temperature and an increase in the ionic strength of the melt.
KEYWORDS
molybdenum, thermodynamics, high temperature corrosion, melts
DOI:10.31857/S0235010620030032