Crevice Corrosion on Ni-Cr-Mo Alloys

Jakupi, P. ; Zagidulin, D. ; Noel, J.J. ; Shoesmith, D.W.

United States. Department of Energy. Yucca Mountain Project Office.

关键词: Corrosion;    Alloys;    Crevice Corrosion;    Radioactive Wastes;    Scanning Electron Microscopy;   

DOI  :  10.2172/893712
RP-ID  :  NA
RP-ID  :  NA
RP-ID  :  893712

美国|英语

来源: UNT Digital Library

【 摘 要 】

Ni-Cr-Mo alloys were developed for their exceptional corrosion resistance in a variety of extreme corrosive environments. An alloy from this series, Alloy-22, has been selected as the reference material for the fabrication of nuclear waste containers in the proposed Yucca Mountain repository located in Nevada (US). A possible localized corrosion process under the anticipated conditions at this location is crevice corrosion. therefore, it is necessary to assess how this process may, or may not, propagate if the use of this alloy is to be justified. Consequently, the primary objective is the development of a crevice corrosion damage function that can be used to assess the evolution of material penetration rates. They have been using various electrochemical methods such as potentiostatic, galvanostatic and galvanic coupling techniques. Corrosion damage patterns have been investigated using surface analysis techniques such as scanning electron microscopy (SEM) and optical microscopy. All crevice corrosion experiments were performed at 120 C in 5M NaCl solution. Initiating crevice corrosion on these alloys has proven to be difficult; therefore, they have forced it to occur under either potentiostatic or galvanostatic conditions.