Surface damage in ultrafine and multimodal grained tungsten materials induced by low energy helium irradiation

Osman El-Atwani, Mert Efe, Bryan Heim, Jean Paul Allain

Research output: Contribution to journalArticle

Abstract

Although tungsten is considered the best candidate as a plasma facing component (PFC) in the divertor region in the International Thermonuclear Experimental Reactor (ITER), severe morphology changes such as cavities, blisters, bubbles and nanostructure formation are expected. Increasing defect sinks in the tungsten microstructure is one of the possible solutions to mitigate the irradiation damage. In this work, helium irradiation at low energy (50 and 200 eV) and temperatures of 600 (threshold of vacancy migration) and 950 °C were performed on multimodal and ultrafine grained tungsten prepared by spark plasma sintering and severe plastic deformation (SPD), respectively. The multimodal samples consisted of small grains (300-700 nm size) juxtaposed to larger grains (1-3 μm size). Detachment of the small grains was observed in the multimodal grained tungsten irradiated at 600 °C and a fluence of 1 × 1022 m-2 due to grain boundary grooving. On the same sample but at 950 °C, detachment and nanostructuring of the small grains were observed together with recrystallization of the large grains. Irradiation of the SPD samples at 200 eV and 950 °C to a fluence of about 2 × 1022 m-2, resulted in nanostructuring of the ultrafine grained shear bands in the microstructure.

LanguageEnglish (US)
Pages170-177
Number of pages8
JournalJournal of Nuclear Materials
Volume434
Issue number1-3
DOIs
StatePublished - Jan 7 2013

Fingerprint

Helium
Tungsten
tungsten
helium
Irradiation
damage
irradiation
detachment
plastic deformation
Plastic deformation
fluence
energy
grooving
blisters
Experimental reactors
microstructure
Microstructure
Spark plasma sintering
Shear bands
sparks

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Materials Science(all)
  • Nuclear Energy and Engineering

Cite this

Surface damage in ultrafine and multimodal grained tungsten materials induced by low energy helium irradiation. / El-Atwani, Osman; Efe, Mert; Heim, Bryan; Allain, Jean Paul.

In: Journal of Nuclear Materials, Vol. 434, No. 1-3, 07.01.2013, p. 170-177.

Research output: Contribution to journalArticle

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