Study on Corrosion of Austenitic Stainless Steel by Uranyl Salt Solution

Abstract

Applying surface radioactivity measurement, auto-radiographic method and weightless method, the corrosion resistance of some austenitic Cr-Ni steels against uranyl salt solution has been investigated. It was concluded that the count number and the auto-radiographic method are useful to study the initial stage of corrosion mechanism. An X-ray diffractometer study was also made on welded specimens to examine the carbide precipitation and the ferrite formation, and the Nb-carbide precipitated in the matrix was easily detected by an X-ray diffractometer study. The relative abundance of Nb-carbide is less in the welded portion than in the other portion of base metal, and in the welded specimens, there is no ferrite phase. Niobium-stabilized steels always show good corrosion resistance against uranyl salt solution. Some of the specimens were neutron-irradiated (10¹² cm²/sec, 8 MeV) at about room temperature, and the irradiated specimens showed no change in the structure and the corrosion characteristics.