Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions

Heikki Leinonen, Pekka Pohjanne, J. Romu, T. Saukkonen, T. Schildt, H. Hänninen

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

2 Citations (Scopus)

Abstract

The role of de-alloying in stress corrosion cracking (SCC) of the austenitic EN1.4301 (UNS S30400) and duplex stainless steels EN 1.4362 (UNS S32304) and EN 1.4462 (UNS S32205) was evaluated in simulated hot liquor environments.
The samples were tested at 190ºC using U-bend specimens in 100 g NaOH + 55 g Na2S and 15 g NaOH + 150 g Na2S caustic environments simulating hot white (HWL) and hot black (HBL) liquors, respectively. SCC and general corrosion was detected in the steel surface layers.
In austenitic stainless steels, severe cracking was observed throughout the samples in both solutions. In duplex stainless steels, cracking was observed only in the affected surface layer in both solutions. In EN 1.4301 steel, selective dissolution of Fe and Cr and enrichment of Cr, Ni, S, O and Na was observed in the affected surface layer and on the wakes of the large SCC cracks depending on the solution. In HWL, Na was clearly enriched and Cr was both selectively dissolved and enriched at different parts of the affected surface layers.
In HBL, Na enrichment was lower and Cr was selectively dissolved in the affected surface layers.
In the duplex stainless steels EN 1.4362 and EN 1.4462, dissolution of Fe, Cr and Mo and/or enrichment of Ni, Cr, Mo, Na, S and O took place depending on the steel and test solution. Cr content of both steels remained unaffected in HBL.
In HWL, Cr was enriched in the surface layer in the Mo-alloyed steel (EN1.4462) and remained unaffected in the non-Mo-alloyed steel (EN 1.4362).
In HWL, Mo dissolved selectively from the affected surface layer, whereas in HBL Mo enriched in the surface layer in the Mo-alloyed steel.
Na was enriched in the affected surface layer of both duplex stainless steels immersed in HWL.
Original languageEnglish
Title of host publicationCorrosion conference and expo 2012
Pages1364-1375
Volume2
Publication statusPublished - 2012
MoE publication typeA4 Article in a conference publication
EventCorrosion conference and expo 2012: NACE International corrosion 2012 conference and expo - Salt Lake City, United States
Duration: 11 Mar 201215 Mar 2012

Publication series

NameNACE - International Corrosion Conference Series
Volume2
ISSN (Print)0361-4409

Conference

ConferenceCorrosion conference and expo 2012
Abbreviated titleCORROSION2012
CountryUnited States
CitySalt Lake City
Period11/03/1215/03/12

Fingerprint

duplex
corrosion
steel
dissolution
sulfide
sodium
surface layer
cracking (fracture)
crack

Keywords

  • Alkaline solution
  • EDS analyses
  • selective dissolution
  • sodium sulfide
  • stainless steel
  • stress corrosion cracking

Cite this

Leinonen, H., Pohjanne, P., Romu, J., Saukkonen, T., Schildt, T., & Hänninen, H. (2012). Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions. In Corrosion conference and expo 2012 (Vol. 2, pp. 1364-1375). NACE - International Corrosion Conference Series
Leinonen, Heikki ; Pohjanne, Pekka ; Romu, J. ; Saukkonen, T. ; Schildt, T. ; Hänninen, H. / Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions. Corrosion conference and expo 2012. Vol. 2 2012. pp. 1364-1375 (NACE - International Corrosion Conference Series).
@inproceedings{9d147f5c358748c4822aced03aae637c,
title = "Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions",
abstract = "The role of de-alloying in stress corrosion cracking (SCC) of the austenitic EN1.4301 (UNS S30400) and duplex stainless steels EN 1.4362 (UNS S32304) and EN 1.4462 (UNS S32205) was evaluated in simulated hot liquor environments. The samples were tested at 190ºC using U-bend specimens in 100 g NaOH + 55 g Na2S and 15 g NaOH + 150 g Na2S caustic environments simulating hot white (HWL) and hot black (HBL) liquors, respectively. SCC and general corrosion was detected in the steel surface layers. In austenitic stainless steels, severe cracking was observed throughout the samples in both solutions. In duplex stainless steels, cracking was observed only in the affected surface layer in both solutions. In EN 1.4301 steel, selective dissolution of Fe and Cr and enrichment of Cr, Ni, S, O and Na was observed in the affected surface layer and on the wakes of the large SCC cracks depending on the solution. In HWL, Na was clearly enriched and Cr was both selectively dissolved and enriched at different parts of the affected surface layers. In HBL, Na enrichment was lower and Cr was selectively dissolved in the affected surface layers. In the duplex stainless steels EN 1.4362 and EN 1.4462, dissolution of Fe, Cr and Mo and/or enrichment of Ni, Cr, Mo, Na, S and O took place depending on the steel and test solution. Cr content of both steels remained unaffected in HBL. In HWL, Cr was enriched in the surface layer in the Mo-alloyed steel (EN1.4462) and remained unaffected in the non-Mo-alloyed steel (EN 1.4362). In HWL, Mo dissolved selectively from the affected surface layer, whereas in HBL Mo enriched in the surface layer in the Mo-alloyed steel. Na was enriched in the affected surface layer of both duplex stainless steels immersed in HWL.",
keywords = "Alkaline solution, EDS analyses, selective dissolution, sodium sulfide, stainless steel, stress corrosion cracking",
author = "Heikki Leinonen and Pekka Pohjanne and J. Romu and T. Saukkonen and T. Schildt and H. H{\"a}nninen",
year = "2012",
language = "English",
isbn = "978-1-6227-6078-7",
volume = "2",
series = "NACE - International Corrosion Conference Series",
pages = "1364--1375",
booktitle = "Corrosion conference and expo 2012",

}

Leinonen, H, Pohjanne, P, Romu, J, Saukkonen, T, Schildt, T & Hänninen, H 2012, Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions. in Corrosion conference and expo 2012. vol. 2, NACE - International Corrosion Conference Series, pp. 1364-1375, Corrosion conference and expo 2012, Salt Lake City, United States, 11/03/12.

Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions. / Leinonen, Heikki; Pohjanne, Pekka; Romu, J.; Saukkonen, T.; Schildt, T.; Hänninen, H.

Corrosion conference and expo 2012. Vol. 2 2012. p. 1364-1375 (NACE - International Corrosion Conference Series).

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingsScientificpeer-review

TY - GEN

T1 - Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions

AU - Leinonen, Heikki

AU - Pohjanne, Pekka

AU - Romu, J.

AU - Saukkonen, T.

AU - Schildt, T.

AU - Hänninen, H.

PY - 2012

Y1 - 2012

N2 - The role of de-alloying in stress corrosion cracking (SCC) of the austenitic EN1.4301 (UNS S30400) and duplex stainless steels EN 1.4362 (UNS S32304) and EN 1.4462 (UNS S32205) was evaluated in simulated hot liquor environments. The samples were tested at 190ºC using U-bend specimens in 100 g NaOH + 55 g Na2S and 15 g NaOH + 150 g Na2S caustic environments simulating hot white (HWL) and hot black (HBL) liquors, respectively. SCC and general corrosion was detected in the steel surface layers. In austenitic stainless steels, severe cracking was observed throughout the samples in both solutions. In duplex stainless steels, cracking was observed only in the affected surface layer in both solutions. In EN 1.4301 steel, selective dissolution of Fe and Cr and enrichment of Cr, Ni, S, O and Na was observed in the affected surface layer and on the wakes of the large SCC cracks depending on the solution. In HWL, Na was clearly enriched and Cr was both selectively dissolved and enriched at different parts of the affected surface layers. In HBL, Na enrichment was lower and Cr was selectively dissolved in the affected surface layers. In the duplex stainless steels EN 1.4362 and EN 1.4462, dissolution of Fe, Cr and Mo and/or enrichment of Ni, Cr, Mo, Na, S and O took place depending on the steel and test solution. Cr content of both steels remained unaffected in HBL. In HWL, Cr was enriched in the surface layer in the Mo-alloyed steel (EN1.4462) and remained unaffected in the non-Mo-alloyed steel (EN 1.4362). In HWL, Mo dissolved selectively from the affected surface layer, whereas in HBL Mo enriched in the surface layer in the Mo-alloyed steel. Na was enriched in the affected surface layer of both duplex stainless steels immersed in HWL.

AB - The role of de-alloying in stress corrosion cracking (SCC) of the austenitic EN1.4301 (UNS S30400) and duplex stainless steels EN 1.4362 (UNS S32304) and EN 1.4462 (UNS S32205) was evaluated in simulated hot liquor environments. The samples were tested at 190ºC using U-bend specimens in 100 g NaOH + 55 g Na2S and 15 g NaOH + 150 g Na2S caustic environments simulating hot white (HWL) and hot black (HBL) liquors, respectively. SCC and general corrosion was detected in the steel surface layers. In austenitic stainless steels, severe cracking was observed throughout the samples in both solutions. In duplex stainless steels, cracking was observed only in the affected surface layer in both solutions. In EN 1.4301 steel, selective dissolution of Fe and Cr and enrichment of Cr, Ni, S, O and Na was observed in the affected surface layer and on the wakes of the large SCC cracks depending on the solution. In HWL, Na was clearly enriched and Cr was both selectively dissolved and enriched at different parts of the affected surface layers. In HBL, Na enrichment was lower and Cr was selectively dissolved in the affected surface layers. In the duplex stainless steels EN 1.4362 and EN 1.4462, dissolution of Fe, Cr and Mo and/or enrichment of Ni, Cr, Mo, Na, S and O took place depending on the steel and test solution. Cr content of both steels remained unaffected in HBL. In HWL, Cr was enriched in the surface layer in the Mo-alloyed steel (EN1.4462) and remained unaffected in the non-Mo-alloyed steel (EN 1.4362). In HWL, Mo dissolved selectively from the affected surface layer, whereas in HBL Mo enriched in the surface layer in the Mo-alloyed steel. Na was enriched in the affected surface layer of both duplex stainless steels immersed in HWL.

KW - Alkaline solution

KW - EDS analyses

KW - selective dissolution

KW - sodium sulfide

KW - stainless steel

KW - stress corrosion cracking

M3 - Conference article in proceedings

SN - 978-1-6227-6078-7

VL - 2

T3 - NACE - International Corrosion Conference Series

SP - 1364

EP - 1375

BT - Corrosion conference and expo 2012

ER -

Leinonen H, Pohjanne P, Romu J, Saukkonen T, Schildt T, Hänninen H. Selective dissolution and stress corrosion cracking susceptibility of austenitic and duplex stainless steels in sodium sulfide containing alkaline solutions. In Corrosion conference and expo 2012. Vol. 2. 2012. p. 1364-1375. (NACE - International Corrosion Conference Series).