Helium bubble distributions in a nanostructured ferritic alloy
2013 (English)In: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 434, no 1-3, 210-216 p.Article in journal (Refereed) Published
A 14YWT nanostructured ferritic alloy (NFA) was implanted with He + ions to fluences of 6.75 × 1021 He m-2 at 400 °C in order to simulate the effects of high He concentrations produced in advanced fission and future fusion reactors at an accelerated timescale. The He bubble size distributions associated with specific microstructural features were characterized by a combination of transmission electron microscopy and atom probe tomography. Helium bubbles were observed on grain boundaries, dislocations, and on the surfaces of nanoclusters and larger Ti(N,C) precipitates. A polydisperse distribution of bubble sizes was observed in the ferrite matrix. With the exception of He bubbles on dislocations, bubbles were observed to increase in size with increasing fluence. The combined TEM and APT data indicates that ∼4.4% of the bubbles are located on coarse precipitates, ∼12.2% at dislocations, ∼14.4% at grain boundaries, and ∼48.6% on nanoclusters, and the remainder as isolated bubbles in the ferrite matrix. The abundances of these different trapping sites, especially the nanoclusters, might reduce the availability and mobility of He, and possibly the susceptibility of these alloys to He embrittlement.
Place, publisher, year, edition, pages
2013. Vol. 434, no 1-3, 210-216 p.
Atom probe tomography, Bubble size, Ferrite matrix, Ferritic alloys, Fluences, He bubbles, Helium bubbles, Isolated bubbles, Microstructural features, Nano-structured, Polydisperses, Time-scales, Trapping sites, Ferrite, Fusion reactors, Grain boundaries, Microstructural evolution, Nanoclusters, Nanostructured materials, Transmission electron microscopy, Helium
Engineering and Technology
IdentifiersURN: urn:nbn:se:kth:diva-118115DOI: 10.1016/j.jnucmat.2012.11.049ISI: 000315752000027ScopusID: 2-s2.0-84871755302OAI: oai:DiVA.org:kth-118115DiVA: diva2:604863
QC 201302122013-02-122013-02-122013-04-04Bibliographically approved