Susceptibility of 304 Stainless Steel to Crevice Corrosion in Electrochemically Active Fluids

CORROSION ◽  
10.5006/3324 ◽  
2020 ◽  
Vol 76 (4) ◽  
pp. 424-435
Author(s):  
Abinaya Kamaraj ◽  
Johann Wilhelm Erning
Keyword(s):  
Stainless Steel ◽  
Crevice Corrosion ◽  
Chloride Concentration ◽  
304 Stainless Steel ◽  
Water Composition ◽  
Polyether Ether Ketone ◽  
Electrochemically Active ◽  
Ether Ketone ◽  
Type 304 ◽  
Type 304 Stainless Steel

The susceptibility of Type 304 stainless steel (SS) to crevice corrosion upon contacting with electrochemically active fluids was investigated using exposure tests and stepwise potentiostatic polarization. Crevice materials made of 304 SS and polyether ether ketone (PEEK) were focused on in this study. The combined influence of oxidant and chloride concentration on crevice corrosion was examined in detail in the two types of crevice combinations (304 SS-to-PEEK and 304 SS-to-304 SS). The 304 SS specimens were strongly susceptible to crevice corrosion when coupled with 304 SS. Even at a low concentration of 5 mg/L free chlorine and 150 mg/L chloride, which is below nominal dilutions in beverage industries, the examined specimens underwent crevice corrosion in both crevices. The effect of water composition on crevice corrosion was also studied, indicating high susceptibility of 304 SS to crevice corrosion in low pH (pH ≤ 5) solutions. The corroded surface morphology was analyzed using scanning electron microscope, energy dispersive x-ray, and confocal microscope.

Effects of Chloride, Bromide, and Thiosulfate Ions on the Critical Conditions for Crevice Corrosion of Several Stainless Alloys as a Material for Geological Disposal Packages for Nuclear Waste

1992 ◽  
Vol 294 ◽  
Author(s):  
Guen Nakayama ◽  
Hisao Wakamatsu ◽  
Masatsune Akashi
Keyword(s):  
Stainless Steel ◽  
Nuclear Waste ◽  
Crevice Corrosion ◽  
304 Stainless Steel ◽  
Critical Conditions ◽  
Geological Disposal ◽  
Steel Type ◽  
316 Stainless Steel ◽  
Type 304 ◽  
Type 304 Stainless Steel

ABSTRACTIn addition to mild steel, several stainless alloys are being proposed as materials for packages for geological disposal of high-level nuclear waste. When buried deep underground, the greatest detriment to the integrity of packages made of these alloys is localized corrosion, for which critical conditions for initiation of crevice corrosion in chloride environments, with or without other ions, need be precisely known.Crevice corrosion behavior of Type 304 stainless steel, Type 316 stainless steel, Alloy 825, Ti-Gr.1, and Ti-Gr.12 in solutions containing ions of chloride, bromide (these two for their ordinary presence in natural waters), or thiosulphate (this for the likelihood of microbially influenced corrosion) to varying concentrations have been empirically examined. All of these alloys exhibit much the same concentration dependency of crevice corrosion sensitivity for chloride and bromide ions, while Type 304 stainless steel is particularly sensitive to the thiosulphate ion. The region of insensitivity for chloride ion is wider in the increasing order of Type 304 stainless steel, Type 316 stainless steel, Ti-Gr. 1, and Ti-Gr. 12, with that of Alloy 825 lying somewhere in between.

scholarly journals Factorial Design based Optimisation of Crevice Corrosion for Type 304 Stainless Steel in Chloride Solutions

2016 ◽  
Vol 16 (2) ◽  
pp. 5-20
Author(s):  
O.O. Ogunleye ◽  
A.G. Adeniyi ◽  
M.O. Durowoju
Keyword(s):  
Stainless Steel ◽  
Factorial Design ◽  
Immersion Time ◽  
Chloride Concentration ◽  
Scaling Factor ◽  
304 Stainless Steel ◽  
Percentage Area ◽  
Type 304 ◽  
Type 304 Stainless Steel ◽  
Ss 304

Abstract The effects of chloride concentration, creviced scaling factor and immersion time on the percentage area and maximum depth of attack for Type 304 stainless steel (SS304) in chloride solutions were investigated. The crevice assembly comprised of coupon (SS-304), polytetrafluoroethylene (crevice former) and fasteners (titanium bolt, nut and washers). The full immersion tests were based on ASTM G-78 using full factorial design to study the effects of chloride concentration (1.5, 3.0 and 4.5 w/w%), crevice scaling factor (8, 16 and 24) and immersion time (15, 30 and 45 days) on the percentage area of attack (Y1) and maximum depth of attack (Y2) of SS-304. Data obtained was used to develop and optimize the models of Y1 and Y2 in terms of the three factors using Response Surface Methodology (RSM). The R2 of Y1 and Y2 were 0.98 and 0.91, respectively. The minimum Y1 (5.63%) and Y2 (3.32×10−7 mm) were obtained at 4.5% chloride concentration, 20 scaling factor and 15 days immersion time. The predicted optimal conditions agreed with the experimental results for validation with a maximum absolute relative error of 5.75%.

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