Modeling the Effects of Crevice Former, Partculates, and the Evolving Surface Profile in Crevice Corrsion

Landau, U. ; Agarwal, A.S. ; Shan, X. ; Payer, J.H.

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

关键词: Corrosion;    Particulates;    Alloys;    Corrosion Resistant Alloys;    Crevice Corrosion;   

DOI  :  10.2172/893810
RP-ID  :  NA
RP-ID  :  NA
RP-ID  :  893810

美国|英语

来源: UNT Digital Library

【 摘 要 】

Crevice corrosion is an important mode of localized corrosion to be evaluated for the long-term performance of corrosion resistant alloys in high temperature, aqueous environments. This work focuses on the evolution of corrosion damage of Ni-Cr-Mo alloys in hot brines. For the initiation of crevice corrosion, a critical crevice chemistry must develop within the crevice to break down the passive film. The geometry of the crevice and particularly the height of the crevice gap is an important parameter, with tighter crevices being more aggressive. Crevice corrosion models mostly define a smooth walled crevice of uniform gap and do not account for the changing profile after crevice corrosion has initiated. As a complement to the earlier models of the cathodic region, they focus here on the crevice (anodic) region and apply current and potential distribution models to examine the effects of the perturbed surface topography. The analysis focuses on three related issues: (1) the effects surface roughness of the metal and the crevice former, (2) the effects of particulate within the crevice, and (3) the evolution of the crevice profile in the active, anodic region.