Crevice corrosion propagation on alloy 625 and alloy C276 in natural seawater

Journal Article · Wed Oct 01 04:00:00 EDT 1997 · Corrosion

DOI:https://doi.org/10.5006/1.3290259· OSTI ID:543524

McCafferty, E; Bogar, F D; Thomas, II, E D; Creegan, C A ^[1]; Lucas, K E ^[2]; Kaznoff, A I ^[3]

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1. Naval Research Lab., Washington, DC (United States)
2. Naval Research Lab., Key West, FL (United States)
3. Naval Sea Systems Command, Arlington, VA (United States)

Chemical composition of the aqueous solution within crevices on two different Ni-Cr-Mo-Fe alloys immersed in natural seawater was determined using a semiquantitative thin-layer chromatographic method. Active crevices were found to contain concentrated amounts of dissolved Ni{sup 2+}, Cr{sup 3+}, Mo{sup 3+}, and Fe{sup 2+} ions. Propagation of crevice corrosion for the two alloys was determined from anodic polarization curves in model crevice solutions based upon stoichiometric dissolution or selective dissolution of alloy components. Both alloys 625 (UNS N06625) and C276 (UNS N10276) underwent crevice corrosion in the model crevice electrolytes. For the model crevice solution based upon selective dissolution of alloy constituents, the anodic dissolution rate for alloy 625 was higher than that for alloy C276. This trend was reversed for the model crevice solution based upon uniform dissolution of alloy constituents.

• Sponsoring Organization: USDOE
• OSTI ID: 543524
• Journal Information: Corrosion, Journal Name: Corrosion Journal Issue: 10 Vol. 53; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHROMATOGRAPHY
CHROMIUM
CREVICE CORROSION
DISSOLUTION
ELECTROLYTES
IRON ALLOYS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
PH VALUE
SEAWATER