EFFECT OF ALLOYING ELEMENTS ON PROCLIVITY OF ZIRCONIUM ALLOYS FOR NODULAR CORROSION

摘要

An approach to assessing the effect of alloying elements on the proclivity of zirconium alloys for nodular corrosion is described. The approach is based on an analysis of the stability of the corrosion front. The results of a simplified analysis for iron and nickel additives to Zircaloy-2 and -4 are in agreement with the experimental data. The approach described can also be used for zirconium-niobium alloys, but this requires taking account of the mutual effect of the atoms of niobium and other alloying substances. For detailed quantitative assessments of the effect of alloying elements on the proclivity of zirconium alloys for nodular corrosion, the stability analysis must be expanded and including the use of self-consistent numerical models which take account of radiation effects and oxygen transfer through the oxide film.