Effects of Mn addition on dislocation loop formation in A533B and model alloys

H. Watanabe, S. Masaki, S. Masubuchi, N. Yoshida, K. Dohi

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)


It is well known that the radiation hardening or embrittlement of pressure vessel steels is very sensitive to the contents of minor solutes. To study the effect of dislocation loop formation on radiation hardening in these steels, in situ observation using a high-voltage electron microscope was conducted for the reference pressure vessel steel JRQ and Fe-based model alloys containing Mn, Si, and Ni. In the Fe-based model alloys, the addition of Mn was most effective for increasing dislocation loop density at 290 °C. Based on the assumption that a di-interstitial was adopted as the nucleus for the formation of an interstitial loop, a binding energy of 0.22 eV was obtained for the interaction of a Mn atom and an interstitial. The formation of Mn clusters detected by three-dimensional atom probe and interstitial-type loops at room temperature clearly showed that the oversized Mn atoms migrate through an interstitial mechanism. The temperature and flux dependence of loop density in pressure vessel steels was very weak up to 290 °C. This suggests that interstitial atoms are deeply trapped by the radiation-induced solute clusters in pressure vessel steels.

Original languageEnglish
Pages (from-to)268-275
Number of pages8
JournalJournal of Nuclear Materials
Issue number1-3
Publication statusPublished - 2013

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • General Materials Science
  • Nuclear Energy and Engineering


Dive into the research topics of 'Effects of Mn addition on dislocation loop formation in A533B and model alloys'. Together they form a unique fingerprint.

Cite this