Changes in the Burgers vector of perfect dislocation loops without contact with the external dislocations.
We report the observations of a new type of changing process in the Burgers vector of dislocations by in situ transmission electron microscopy. Small interstitial-type perfect dislocation loops in bcc iron with diameters less than approximately 50 nm are transformed from a 1/2<111> loop to another 1/2<111> one or an energetically unfavorable <100> one; furthermore, a <100> loop is transformed to a 1/2<111> one. These transformations occurred on high-energy electron irradiation or simple heating without contact with external dislocations. The origin of these phenomena is discussed.
Arakawa
K
K
Research Center for Ultra-High Voltage Electron Microscopy, Osaka University, 7-1, Mihogaoka, Ibaraki, Osaka 567-0047, Japan. arakawak@uhvem.osaka-u.ac.jp
Hatanaka
M
M
Kuramoto
E
E
Ono
K
K
Mori
H
H