Weak-beam scanning transmission electron microscopy for quantitative dislocation density measurement in steels

Research output: Contribution to journalArticle


Institutes & Expert groups

  • Tohoku University - Institute for Materials Research
  • Kyoto University
  • Tractebel - Engie

Documents & links



To evaluate dislocations induced by neutron irradiation, we developed a weak-beam scanning transmission electron microscopy (WB-STEM) system by installing a novel beam selector, an annular detector, a high-speed CCD camera and an imaging filter in the camera chamber of a spherical aberration-corrected transmission electron microscope. The capabilities of the WB-STEM with respect to wide-view imaging, real-time diffraction monitoring and multi-contrast imaging are demonstrated using typical reactor pressure vessel steel that had been used in an European nuclear reactor for 30 years as a surveillance test piece with a fluence of 1.09 × 1020 neutronscm–2. The quantitatively measured size distribution (average loop size = 3.6 ± 2.1 nm), number density of the dislocation loops (3.6 × 1022m−3) and dislocation density (7.8 × 1013mm–3) were carefully compared with the values obtained via conventional weak-beam transmission electron microscopy studies. In addition, cluster analysis using atom probe tomography (APT) further demonstrated the potential of the WB-STEM for correlative electron tomography/ APT experiments


Original languageEnglish
Article number66
Pages (from-to)120-130
Number of pages10
JournalJournal of Microscopy
Issue number2
Publication statusPublished - 18 Jan 2017


  • TEM, wek-beam, dislocation , density

ID: 5644064