Localized corrosion of Alloy 600 in thiosulfate solution at 25C

Journal Article · Thu Jul 01 04:00:00 EDT 1993 · Corrosion (Houston); (United States)

DOI:https://doi.org/10.5006/1.3316087· OSTI ID:6254431

Yang, I J ^[1]

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1. Materials Research Labs., Hsinchu (Taiwan, Province of China)

The integrity of the passive film formed on an untreated alloy in thiosulfate solution was investigated by adding small amounts of dilute chloride ions. Linearity of corrosion potential was obtained in the range of 1 to 0.001 M sodium thiosulfate (Na[sub 2]S[sub 2]O[sub 3]) as a function of the concentration of chloride ion. The chloride content needed to generate pitting decreased as the logarithm of the deaerated thiosulfate concentration decreased. Fractography showed ductile fractures for an untreated UNS N06600 alloy (Alloy 600) and intergranular stress corrosion cracking (SCC) or intergranular attack for sensitized Alloy 600. These were dependent upon potential. The failure time showed a minimum at 10[sup [minus]4]M Na[sub 2]S[sub 2]O[sub 3]. The fracture mechanism was correlated with the active loop regime, where vigorous dissolution reactions were produced during repassivation. unsensitized Alloy 600 in thiosulfate ions was not susceptible to SCC when potential was controlled at [minus]300mV[sub SCE] or at +400mV[sub SCE].

• OSTI ID: 6254431
• Journal Information: Corrosion (Houston); (United States), Journal Name: Corrosion (Houston); (United States) Vol. 49:7; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360105* -- Metals & Alloys-- Corrosion & Erosion
ALKALI METAL COMPOUNDS
ALLOY-NI76CR15FE8
ALLOYS
ALUMINIUM ADDITIONS
ALUMINIUM ALLOYS
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
CHROMIUM ALLOYS
CORROSION
CORROSION RESISTANT ALLOYS
CORROSIVE EFFECTS
DATA
ELECTRIC POTENTIAL
EXPERIMENTAL DATA
FAILURES
FRACTOGRAPHY
FRACTURE MECHANICS
FRACTURE PROPERTIES
FRACTURES
HALIDES
HALOGEN COMPOUNDS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
INCONEL 600
INCONEL ALLOYS
INFORMATION
INTERGRANULAR CORROSION
IRON ALLOYS
MATERIALS
MECHANICAL PROPERTIES
MECHANICS
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIMONIC
NUMERICAL DATA
PASSIVATION
PITTING CORROSION
SODIUM COMPOUNDS
STRESS CORROSION
THIOSULFATES
TITANIU
TITANIUM ADDITIONS