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Pitting Corrosion Behavior of F304 Stainless Steel Under the Exposure of Ferric Chloride Solution

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Surinder Pal
Surinder Pal
Surinder Pal
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Shailendra Singh Bhadauria at Dr. B. R. Ambedkar National Institute of Technology Jalandhar
Shailendra Singh Bhadauria
Pramod Kumar Kushwaha at Dr. B. R. Ambedkar National Institute of Technology Jalandhar
Pramod Kumar Kushwaha
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Present paper deals with an experimental investigation of pitting corrosion of forged 304 stainless steel. Material is exposed to ferric chloride solution to investigate the effect of pitting corrosion. This material is known to provide structural strength with improved toughness and ductility. A number of experiments were carried out on F304 SS under ferric chloride solution by putting it for three different time durations of 8 h, 16 h, and 24 h. The results specify that pit formation increases over time. During experimentation, the number of pits, pit depth, corrosion rate, weight loss, and average pit depth have been measured. Microstructural characterization and surface roughness tests were carried out on the chemically exposed surface to understand the growth of pitting corrosion. Fractographic images high-end microscopy showed that the ferric chloride solution initiates the pitting of 304 austenite stainless steel. Furthermore, the exposure leads to the formation of a number of small pits that coalescence together to form cracks that appear at the bottom of the pit. It was also confirmed that the appearance of small bottom pits initiates cracks by increasing the duration of corrosion test to 24 h which is only due to dissolved inclusive atoms of chloride as revealed by EDX analysis.
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Vol.:(0123456789)
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Journal of Bio- and Tribo-Corrosion (2019) 5:91
https://doi.org/10.1007/s40735-019-0283-z
Pitting Corrosion Behavior ofF304 Stainless Steel Under theExposure
ofFerric Chloride Solution
SurinderPal1 · ShailendraSinghBhadauria1,2· PramodKumar2
Received: 19 June 2019 / Revised: 14 August 2019 / Accepted: 27 August 2019 / Published online: 9 September 2019
© Springer Nature Switzerland AG 2019
Abstract
Present paper deals with an experimental investigation of pitting corrosion of forged 304 stainless steel. Material is exposed
to ferric chloride solution to investigate the effect of pitting corrosion. This material is known to provide structural strength
with improved toughness and ductility. A number of experiments were carried out on F304 SS under ferric chloride solution
by putting it for three different time durations of 8h, 16h, and 24h. The results specify that pit formation increases over
time. During experimentation, the number of pits, pit depth, corrosion rate, weight loss, and average pit depth have been
measured. Microstructural characterization and surface roughness tests were carried out on the chemically exposed surface
to understand the growth of pitting corrosion. Fractographic images high-end microscopy showed that the ferric chloride
solution initiates the pitting of 304 austenite stainless steel. Furthermore, the exposure leads to the formation of a number of
small pits that coalescence together to form cracks that appear at the bottom of the pit. It was also confirmed that the appear-
ance of small bottom pits initiates cracks by increasing the duration of corrosion test to 24h which is only due to dissolved
inclusive atoms of chloride as revealed by EDX analysis.
Keywords F304 stainless steel· Pitting corrosion· Corrosion rate· Pit depth· Ferric chloride solution
1 Introduction
Austenite stainless steel is widely used for the corrosive
environment. Present work is focused on understanding
the effect of ferric chloride solution on F304 stainless steel
which is widely used for various industrial applications
(such as petroleum, food, medicine, and other industries).
The purpose of this study is to examine the corrosive behav-
ior of the material and to observe its effect with respect to
time. Many researchers have studied corrosion susceptibil-
ity of 304 stainless steel under different chemical solutions
with varying pH and temperatures. Vogiatzis etal. examined
the corrosion behavior of 304 austenitic stainless steel in
simulated oil field produced water at 25°C, and their results
indicated that the corrosion rate is reduced with time [1].
Street etal. analyzed the atmospheric pitting corrosion of
material 304L stainless steel by using droplets of MgCl2 for
24h at temperature 30°C. It was revealed that the pit mor-
phology was a sensitive function of relative humidity (RH)
[2, 3]. Degerbec etal. tested the specimens of steel type
18Cr–2Mo–Ti which were exposed for 1, 3, and 5years in
a marine atmosphere. It was observed that in a near-coastal
area, the stainless steel type 18Cr–2Mo–Ti is well suitable
for usage in building applications [4, 5]. Xie etal. deter-
mined the change in pitting corrosion from the statistics
of pitting during the test duration up to 720h exposed to
highly concentrated chloride solutions. It revealed that the
resistance to pitting corrosion was considerably affected
by chloride concentration and temperature. [6]. Prosek
etal. studied the application limits of different austenitic
and austenitic–ferritic (duplex) stainless steels subjected
to tensile stress. Furthermore, the corrosivity of chloride
deposits under given exposure conditions decreased in the
following order: calcium chloride (CaCl2) > magnesium
* Surinder Pal
Surinder92.pal@gmail.com
Shailendra Singh Bhadauria
bhadauriass@nitj.ac.in
Pramod Kumar
kushwahapramod@nitj.ac.in
1 Department ofIndustrial andProduction Engineering, Dr.
B R Ambedkar National Institute ofTechnology Jalandhar,
Jalandhar, Punjab144011, India
2 Dr. B R Ambedkar, National Institute ofTechnology
Jalandhar, Jalandhar, Punjab144011, India
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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Article
  • Mar 2018
The corrosion behaviour of 2101 duplex stainless steel (DSS) in NaCl solution was studied and compared with that of 2205 DSS. The effects of chloride concentration and solution temperature on pitting corrosion behaviour were focused. The relative sensitivity to pitting corrosion of the constituent phases in both 2101 and 2205 DSSs was also explored. Pitting corrosion susceptibility was evaluated by conducting cyclic polarisation curve measurement. The corrosion morphology was examined by a scanning electron microscope equipped with energy dispersive spectrometer. The experimental results showed that the pitting corrosion resistance of 2101 DSS was inferior to that of 2205 DSS by exhibiting a lower threshold chloride concentration and a lower critical pitting temperature. For both 2101 and 2205 DSSs, the ferrite phase was more susceptible than austenite phase to pitting corrosion. This paper is part of a supplementary issue from the 17th Asia-Pacific Corrosion Control Conference (APCCC-17).
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