Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Effects of hydrogen on the corrosion resistance of metallic materials and semiconductors
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Corrosion Science.
2006 (English)In: High-Temperature Oxidation And Corrosion 2005 / [ed] Taniguchi, S; Maruyama, T; Yoshiba, M; Otsuka, N; Kawahara, Y, 2006, Vol. 522-523, 139-146 p.Conference paper, Published paper (Refereed)
Abstract [en]

For long time it is known that protons in aqueous solutions have a detrimental effect on metallic materials. Relatively recently, it has also been observed in aqueous solution that the pitting corrosion resistance of Cr, stainless steel 304 and 310 decreases and the anodic dissolution rate increases due to the presence of hydrogen in the metal. In gas phase a high oxidation rate has been observed for hydrogen containing Cr and Fe. Hydrogen in the substrate can also enhance the oxidation of Fe in SS 316 and As in GaAs. All these results suggest enhanced dissolution in aqueous solution and enhanced oxide growth at the oxide/gas interface in gas phase oxidation due to hydrogen promoted outward-transport of substrate components. A possible mechanism for such out-transport is an increased metal ion diffusivity in the metal-oxide due to a high abundance of metal ion vacancies generated by hydrogen. In contrast to all the above examples, also positive effects of hydrogen have been identified under certain conditions. In an attempt to understand both the negative and the positive effects the concept of a beneficial, balanced oxide growth is used. In this concept a certain amount of hydrogen can be beneficial in the oxidation by improving the balance between oxygen-ion and metalion transport, leading to more dense and protective oxides. Depending on the temperature, H(2) in air is considered as either a sink or a source for hydrogen in materials.

Place, publisher, year, edition, pages
2006. Vol. 522-523, 139-146 p.
Series
Materials Science Forum, ISSN 0255-5476 ; 522-523
Keyword [en]
hydrogen, gas phase, water, metal diffusion, molecular dissociation, SIMS
National Category
Corrosion Engineering
Identifiers
URN: urn:nbn:se:kth:diva-41990ISI: 000241416500016Scopus ID: 2-s2.0-34548485611ISBN: 0-87849-409-X (print)OAI: oai:DiVA.org:kth-41990DiVA: diva2:445762
Conference
International Symposium on High-Temperature Oxidation and Corrosion 2005 (ISHOC 2005) Location: Nara, Japan, Date: NOV 30-DEC 02, 2005
Note
QC 20111005Available from: 2011-10-05 Created: 2011-10-05 Last updated: 2011-10-05Bibliographically approved
In thesis
1. Modified oxygen and hydrogen transport in Zr-based oxides
Open this publication in new window or tab >>Modified oxygen and hydrogen transport in Zr-based oxides
2006 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Most metals and alloys in the presence of oxygen and moisture will instantaneously react and form a thin (2-5 nm) surface oxide layer. For further reaction to occur, oxygen ions and/or metal cations often diffuse through the already formed oxide layer. The corrosion resistance of a metal in aggressive environments at high temperatures depends on the properties of the surface oxide scale.

Zirconium-based alloys represent the main structural materials used in water-cooled nuclear reactors. For these materials, the formation of a thin, adherent oxide scale with long-term stability in high temperature water/steam under irradiation conditions, is crucial. In this thesis, the transport of oxygen and hydrogen through Zr-based oxide scales at relevant temperatures for the nuclear industry is investigated using isotopic gas mixtures and isotope-monitoring techniques such as Gas Phase Analysis and Secondary Ion Mass Spectrometry.

Porosity development in the oxide scales generates easy diffusion pathways for molecules across the oxide layer during oxidation. A considerable contribution of molecular oxygen to total oxygen transport in zirconia has been observed at temperatures up to 800°C. A novel method for evaluation of the gas diffusion, gas concentration and effective pore size of oxide scales is presented in this thesis. Effective pore sizes in the nanometer range were found for pretransition oxides on Zircaloy-2. A mechanism for densification of oxide scales by obtaining a better balance between inward oxygen and outward metal transport is suggested. Outward Zr transport can be influenced by the presence of hydrogen in the oxide and/or metal substrate. Inward oxygen transport can be promoted by oxygen dissociating elements such as Fe-containing second phase particles. The results suggest furthermore that a proper choice of the second-phase particles composition and size distribution can lead to the formation of dense oxides, which are characterized by low oxygen and hydrogen uptake rates during oxidation.

Hydrogen uptake in Zr-based materials during oxidation in high temperature water/steam can generate degradation due to the formation of brittle hydrides in the metal substrate. A promising method for the suppression of hydrogen uptake has been developed and is presented in this thesis.

Place, publisher, year, edition, pages
Stockholm: KTH, 2006. 48 p.
Keyword
Zirconia, Zirconium, Zircaloy, hydrogen and oxygen diffusion, SPP, oxygen dissociating elements, oxidation, dissociation, hydration, CO adsorption, molecular transport, porosity.
National Category
Materials Engineering
Identifiers
urn:nbn:se:kth:diva-4095 (URN)91-7178-429-2 (ISBN)
Public defence
2006-09-22, F3, Lindstedtsvägen 26, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20100629Available from: 2006-09-08 Created: 2006-09-08 Last updated: 2011-10-05Bibliographically approved

Open Access in DiVA

No full text

Scopus

Search in DiVA

By author/editor
Hultquist, GunnarAnghel, ClaraSzakalos, Peter
By organisation
Corrosion Science
Corrosion Engineering

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 115 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf