Post-irradiation annealing of Ni-Mn-Si-enriched clusters in a neutron-irradiated RPV steel weld using Atom Probe Tomography
2015 (English)In: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 459, 127-134 p.Article in journal (Refereed) Published
Atom Probe Tomography has been performed on as-irradiated and post-irradiation annealed surveillance weld samples from Ringhals Unit 3. The weld contains low Cu (0.07at.%) and high Ni (1.5at.%). A high number density (~4x1023 m-3) of Ni-Mn-Si-enriched clusters was observed in the as-irradiated material. The onset of recovery was observed during the annealing for 30 min at 450°C. Much more significant dissolution of clusters occurred during the 10 minute 500°C anneal, resulting in a reduction in mean cluster size and a halving of their volume fraction.
Detailed analyses of the changes in microstructure demonstrate that the dissolution process is driven by migration of Mn atoms from the clusters. This may indicate a strong correlation between Mn and point defects. Dissolution of the clusters is shown to correlate with recovery of mechanical properties in this material.
Place, publisher, year, edition, pages
2015. Vol. 459, 127-134 p.
Neutron irradiation, Low alloy steels, post irradiation annelaing, atom probe, clustering, materials ageing
Research subject Materials Science and Engineering
IdentifiersURN: urn:nbn:se:kth:diva-164152DOI: 10.1016/j.jnucmat.2015.01.027ISI: 000350710700018ScopusID: 2-s2.0-84921519789OAI: oai:DiVA.org:kth-164152DiVA: diva2:803862
QC 201504142015-04-142015-04-142016-02-09Bibliographically approved