Investigation on Corrosion Behavior and Semiconductor Properties of Oxide Films on SS316L, Inconel600 and Incoloy800 in High Temperature Water with ZnO Addition

摘要

Oxide films on 316L stainless steel, Inconel600 and Incoloy800 were formed in 288C hightemperature water with/without 650ppb ZnO addition. Corrosion resistance and semiconductorproperties of oxide films on alloys after oxidation were characterized by electrochemicalpotentiodynamic polarization and capacitance measurement (Mott-Schottky plot).After oxidation, thesurfaces of alloys with ZnO addition indicated smaller crystals than the ones without ZnO additions,supported by FE-SEM images. XPS suggested an enrichment of Zn with iron and oxygen, under thesurface of oxide film on the alloys. Flat band potential of the oxide films moves to the negativedirection, besides a decreasing of donor density with ZnO addition. Point defect model was employedto investigate the effect of ZnO addition on semiconductor properties of oxide films led to enhancedcorrosion resistance.