Dislocation Loop Formation and Growth under In Situ Laser and/or Electron Irradiation

• Published in: Scientific reports Vol. 1; no. 1; p. 190
• Main Authors: Yang, Zhanbing, Sakaguchi, Norihito, Watanabe, Seiichi, Kawai, Masayoshi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 12-12-2011; Nature Publishing Group
• Subjects: 639/301; 639/301/1034; 639/766/25; 639/766/387; Humanities and Social Sciences; multidisciplinary; Science
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep00190

Vacancies and interstitial atoms are primary lattice (point) defects that cause observable microstructural changes, such as the formation of dislocation loops and voids in crystalline solids. These defects' diffusion properties determine the phase stability and environmental resistibility of macroscopic materials under ambient conditions. Although
in situ
methods have been proposed for measuring the diffusion energy of point defects, direct measurement has been limited. In this study, we propose an alternative
in situ
method to measure the activation energy for vacancy migration under laser irradiation using a pulsed laser beam from a laser-equipped high-voltage electron microscope (laser-HVEM). We made
in situ
observations that revealed the formation and growth of vacancy dislocation loops in an austenitic stainless steel during laser irradiation. These loops continued to grow when thermal annealing was performed after laser irradiation at the same temperature. We anticipate that laser-HVEM will provide a new method for investigating lattice defects.