Effect of [HCO{sub 3}{sup {minus}}+CO{sub 3}{sup 2{minus}}] on corrosion crevice repassivation potential of carbon steel in simulated bentonite environment

Book · Thu Aug 01 04:00:00 EDT 1996

OSTI ID:264465

Fukuda, Takanori; Akashi, Masatsune ^[1]

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1. Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo (Japan). Research Inst.

In order to evaluate the localized corrosion susceptibility of carbon steel in water containing bentonite, the critical pH for depassivation, pH{sub d}, the critical potential for crevice corrosion, E{sub R,CREV}, and the free corrosion potential, Esp, were determined in simulated aqueous solutions of 1 to 100 mmol/L [bicarbonate-carbonate], 1 to 1,000 mmol/L [NaCl], and pH of 7 to 12. The following results were obtained: (1) E{sub R,CREV} increases with increasing [bicarbonate-carbonate] concentration. The relationship can be described as a function of the ratio of [Cl{sup {minus}}/bicarbonate-carbonate], (2) the Esp increases with increasing pH in the passive region, and (3) the pH{sub d} shows [bicarbonate-carbonate] concentration dependency. This paper also discusses the relationship between critical initiation potential for device corrosion of carbon steel, [Cl{sup {minus}}], and [bicarbonate-carbonate] anion. The crevice corrosion that occurs on passivated metals and alloys is characterized by determinable critical initiation potential that can be induced in a potential range nobler than its critical potential.

• OSTI ID: 264465
• Report Number(s): CONF-951155--; ISBN 1-55899-315-0
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
36 MATERIALS SCIENCE
ACID CARBONATES
BENTONITE
BRINES
CARBON STEELS
CATALYTIC EFFECTS
CHLORIDES
CONTAINERS
CREVICE CORROSION
EXPERIMENTAL DATA
HIGH-LEVEL RADIOACTIVE WASTES
PASSIVATION
PH VALUE
RADIOACTIVE WASTE DISPOSAL
UNDERGROUND DISPOSAL