du.sePublikationer
Ändra sökning
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • chicago-author-date
  • chicago-note-bibliography
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Formation of oxide layers on tungsten at low oxygen partial pressures
Högskolan Dalarna, Akademin Industri och samhälle, Materialteknik.ORCID-id: 0000-0001-7938-9909
Visa övriga samt affilieringar
2018 (Engelska)Ingår i: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 506, nr SI, s. 26-34Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

This work focuses on the oxidation of tungsten in inert gas atmospheres containing oxygen and moisture. It is particularly relevant for the European Spallation Source where the tungsten target is cooled by purified helium gas and the 5 MW proton beam can raise the maximum target temperature beyond the threshold for oxidation. Tungsten discs were oxidized isothermally at 400° to 900 °C for 2 h in pure helium and helium mixed with oxygen and water vapor, with varying partial pressures up to 500 Pa. Tungsten was oxidized even with a small amount of oxygen (≤5 ppm) present in industrially pure helium. Non-isothermal oxidation of tungsten foils was carried out in water vapor (∼100 Pa), in situ in an environmental scanning electron microscope. On specimens oxidized in inert gas containing water vapor (2 h, pH2O" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 14.4px; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative;">pH2O ∼790 Pa), Auger electron spectroscopy studies confirmed the presence of a thin oxide layer (40 nm) at 400 °C. At 500 °C the oxide layer was 10 times thicker. A dark, thin and adherent oxide layer was observed below 600 °C. Above this temperature, the growth rate increased substantially and the oxide layer was greenish, thick and porous. Oxide layers with varying stoichiometry were observed, ranging from WO3 at the surface to WO2 at the metal-oxide interface. For comparison, oxidation of tungsten alloysin He-5%O2 was studied. The implications of this work on the design and operation of the helium loop for cooling the target are discussed.

Ort, förlag, år, upplaga, sidor
2018. Vol. 506, nr SI, s. 26-34
Nyckelord [en]
Tungsten, Oxidation, Spallation target
Nationell ämneskategori
Materialteknik
Forskningsämne
Stålformning och ytteknik
Identifikatorer
URN: urn:nbn:se:du-26922DOI: 10.1016/j.jnucmat.2017.12.018ISI: 000432848200005Scopus ID: 2-s2.0-85038857400OAI: oai:DiVA.org:du-26922DiVA, id: diva2:1172214
Konferens
13th International Workshop on Spallation Materials Technology (IWSMT), Chattanooga, USA, 2016
Tillgänglig från: 2018-01-09 Skapad: 2018-01-09 Senast uppdaterad: 2018-06-07Bibliografiskt granskad

Open Access i DiVA

Fulltext saknas i DiVA

Övriga länkar

Förlagets fulltextScopus

Personposter BETA

Surreddi, Kumar Babu

Sök vidare i DiVA

Av författaren/redaktören
Surreddi, Kumar Babu
Av organisationen
Materialteknik
I samma tidskrift
Journal of Nuclear Materials
Materialteknik

Sök vidare utanför DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetricpoäng

doi
urn-nbn
Totalt: 98 träffar
RefereraExporteraLänk till posten
Permanent länk

Direktlänk
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • chicago-author-date
  • chicago-note-bibliography
  • Annat format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annat språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf