scholarly journals The Effect of Deposited Dust on SCC and Crevice Corrosion of AISI 304L Stainless Steel in Saline Environment

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6834
Author(s):  
Chun-Ping Yeh ◽  
Kun-Chao Tsai ◽  
Jiunn-Yuan Huang
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Relative Humidity ◽  
Crevice Corrosion ◽  
Chloride Concentration ◽  
Electron Back Scatter Diffraction ◽  
304L Stainless Steel ◽  
Aisi 304L ◽  
Crack Morphology ◽  
Aisi 304L Stainless Steel

Crevice corrosion has become an important issue of the safety of AISI 304L austenitic stainless steel canister when exposed to the chloride environments located in coastal areas. Moreover, dust deposited on the canister surface may enhance the corrosion effect of 304L stainless steel. In this work, white emery was adopted to simulate the dust accumulated on the as-machined specimen surface. To investigate the effect of deposited white emery, chloride concentration, and relative humidity on the crevice corrosion behavior, an experiment was conducted on 304L stainless steel specimens at 45 °C with 45%, 55%, and 70% relative humidity (RH) for 7000 h. The surface features and crack morphology of the tested 304L stainless steel specimens were examined by SEM equipped with energy-dispersive spectrometry (EDS) and electron back scatter diffraction (EBSD). From the experimental results, a threshold RH for the stress corrosion cracking (SCC) initiation of AISI 304L austenitic stainless steel with different concentrations of chloride was proposed.

scholarly journals Influence of Chloride Concentration on Stress Corrosion Cracking and Crevice Corrosion of Austenitic Stainless Steel in Saline Environments

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5640
Author(s):  
Chun-Ping Yeh ◽  
Kun-Chao Tsai ◽  
Jiunn-Yuan Huang
Keyword(s):  
Stainless Steel ◽  
Relative Humidity ◽  
Crevice Corrosion ◽  
Sea Water ◽  
Safety Concern ◽  
Chloride Concentration ◽  
Test Duration ◽  
304L Stainless Steel ◽  
Spent Fuel ◽  
Saline Environments

Stainless steels are used as canister materials for interim storage of spent fuel. Crevice corrosion has proved to be a safety concern of 304L stainless steel spent fuel canisters, when exposed to the saline environments of coastal sites. To study the effects of chloride concentration and test duration on the crevice corrosion behavior, and the effect of relative humidity on the initiation of discrete SCC cracks, a test program was conducted on the 304L steel specimens sprayed with synthetic sea water of 3.5 wt.%. The salt-deposited specimens, wrapped up with a crevice former to form a crevice configuration, were then exposed to an environment at 45 °C with a pre-set 45%, 55%, and 70% relative humidity (RH), for 400 h and 10,000 h, respectively. The surface features and crack morphology of the tested 304L stainless-steel specimens were examined by energy-dispersive spectrometry (EDS) and electron back scatter diffraction (EBSD). For the specimens deposited with a chloride concentration of 1 g/m2, no cracks were found in the corroded regions after 400-h exposure, whereas SCC cracks were observed with the specimens tested for 10,000 h at all three pre-set relative humidity. The specimens tested at the pre-set relative humidity 45% are characterized with discrete SCC cracks, but, on the other hand, those exposed to the environments of 55% and 70% relative humidity show SCC cracks of distinct features. From the results of 10,000-h tests, it is inferred that the chloride concentration threshold for SCC initiation of 304L stainless steel at 45 °C is between 0.1 g/m2 and 1 g/m2.

Influence of Annealing Process on Recrystallisation Behaviour of a Heavily Cold Rolled AISI 304L Stainless Steel on Ultrafine Grain Formation

2012 ◽  
Vol 715-716 ◽  
pp. 334-339 ◽  
Author(s):  
B. Ravi Kumar ◽  
J.K. Sahu ◽  
S.K. Das
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Thermal Process ◽  
Austenitic Stainless Steels ◽  
Ultrafine Grain ◽  
304L Stainless Steel ◽  
Aisi 304L ◽  
Aisi 304L Stainless Steel ◽  
Grain Formation ◽  
Cold Rolled

AISI 304L austenitic stainless steel was cold rolled to 90% with and no inter-pass cooling to produced 89% and 43% of deformation induced martensite respectively. The cold rolled specimens were annealed by isothermal and cyclic thermal process. The microstructures of the cold rolled and annealed specimens were studied by the electron microscope. The observed microstructural changes were correlated with the reversion mechanism of martensite to austenite and strain heterogeneity of the microstructure. The results indicated possibility of ultrafine austenite grain formation by cyclic thermal process for austenitic stainless steels those do not readily undergo deformation induced martensite. Keywords: Austenitic stainless steel, Grain refinement, Cyclic thermal process, Ultrafine grain

scholarly journals Effects of Relative Humidity on Crevice Corrosion Behavior of 304L Stainless-Steel Nuclear Material in a Chloride Environment

Metals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 1185 ◽  
Author(s):  
Yeh ◽  
Tsai ◽  
Huang
Keyword(s):  
Stainless Steel ◽  
Relative Humidity ◽  
Corrosion Behavior ◽  
Crevice Corrosion ◽  
Salt Spray ◽  
Coastal Region ◽  
Steel Specimen ◽  
Electron Back Scatter Diffraction ◽  
304L Stainless Steel ◽  
Stainless Steel Specimen

In the dry cask storage of spent nuclear fuels, a stainless-steel canister acts as an important barrier for encapsulating spent fuels. As a result, local corrosion behavior of 304L stainless steel has become an issue of concern in the wet coastal region and salt spray environment. The test was conducted after deposition of simulated sea salt particles on the 304L stainless-steel specimen. It was first covered with a crevice former, and then kept at 45 °C with a relative humidity of 45%, 55%, and 70%, respectively. The surface morphologies and electron back scatter diffraction (EBSD) analysis of the corroded region for the 304L stainless-steel specimen are presented in this paper. The goal of this work was to investigate the crevice corrosion behavior of 304L stainless steel under different chloride concentrations and relative humidity conditions. From the experimental results, a threshold relative humidity for stress corrosion cracking (SCC) initiation of 304L stainless steel was proposed.

scholarly journals Effect of Cathodic Polarisation Switch-Off on the Passivity and Stability to Crevice Corrosion of AISI 304L Stainless Steel

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2921
Author(s):  
Varvara Shubina Shubina Helbert ◽  
Andrei Nazarov ◽  
Flavien Vucko ◽  
Nicolas Larché ◽  
Dominique Thierry
Keyword(s):  
Stainless Steel ◽  
Crevice Corrosion ◽  
Cathodic Current Density ◽  
304L Stainless Steel ◽  
Kelvin Probe ◽  
Cathodic Current ◽  
Galvanic Current ◽  
Aisi 304L ◽  
Aisi 304L Stainless Steel ◽  
The Impact

The effects of cathodic polarisation switch-off on the passivation of AISI 304L stainless steel in air and its crevice corrosion susceptibility in 3.5 wt.% NaCl aqueous electrolyte were investigated. Scanning Kelvin probe (SKP) data showed that the oxide film is significantly destabilised and the rate of steel passivation in air is slowed down. Thermal desorption analysis (TDA) highlighted that hydrogen absorption is proportional to the applied cathodic current density. A special crevice corrosion set-up was designed to realise simultaneous reproducible monitoring of potential and galvanic current to study the impact of prior cathodic polarisation on crevice corrosion onset.

Development of Laser Cleaning for Metallic Equipment

2018 ◽  
Author(s):  
L. Carvalho ◽  
W. Pacquentin ◽  
M. Tabarant ◽  
J. Lambert ◽  
A. Semerok ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Laser Scanning ◽  
Surface Defects ◽  
Complex Geometry ◽  
Laser Cleaning ◽  
304L Stainless Steel ◽  
Primary Coolant ◽  
Aisi 304L ◽  
Weight Percentage ◽  
Aisi 304L Stainless Steel

Laser cleaning study was performed on prepared samples using a nanosecond pulsed ytterbium fiber laser. To prepare samples, AISI 304L stainless steel samples were oxidized and implemented with non-radioactive contaminants in a controlled manner. In order to validate the cleaning process for metallic equipment polluted in nuclear installations, two types of contamination with europium (Eu) and with cobalt (Co) were studied. Eu was used as a simulator-product resulting from uranium fission, while Co — as an activation-product of nickel, which is a composing element of a primary coolant system of a reactor. The oxide layers have suffered laser scanning which was followed by the furnace treatment to obtain thicknesses in the range of 100 nm to 1 μm depending on the oxidation parameters [1] with a mean weight percentage of 1% of Eu and 1 % of Co in the volume of the oxide layer. Glow Discharge Optical Emission (GD-OES) and Mass Spectrometry (GD-MS) analyses have been performed to assess the efficiency of the cleaning treatment and to follow the distribution of residual contamination with a detection limit of 0.1mg/kg of Eu and Co. Decontamination rates up to 95.5 % were obtained. One of the identified reasons for this limitation is that the radionuclides are trapped in surface defects like micro cracks [2, 3]. Therefore, cleaning treatments have been applied on surface defects with controlled geometry and a micrometric aperture obtained by laser engraving and juxtaposition of polished sheets of AISI 304L stainless steel. The goal of this study is surface decontamination without either welding or inducing penetration of contamination into the cracks. GD-MS analysis and Scanning Electron Microscopy (SEM) were performed to analyze the efficiency of the treatment and the diffusion of contaminants in this complex geometry.

Sign in / Sign up

Export Citation Format

Share Document