Journal of Electron Microscopy 51:S225-S229 (2002)
© 2002 Oxford University Press
Full-length paper |
A study of the mechanism of the growth and shrinkage of stacking fault tetrahedra using the fluctuation of their size under electron irradiation
Department of Material Science, Interdisciplinary Faculty of Science and Engineering, Shimane University, 1060 Nishikawatsu, Matsue 690-8504,
1Center for Integrated Research in Science and Engineering, Nagoya University, Nagoya 464-8601,
2Department of Applied Physics, School of Engineering, Nagoya University, Nagoya 464-8601 and
3Academic Frontier Research Center for Ultra-high-speed Plastic Deformation, Hiroshima Institute of Technology, Hiroshima 731-5193, Japan
To whom correspondence should be addressed. E-mail: arakawak{at}riko.shimane-u.ac.jp
The growth and shrinkage processes of stacking fault tetrahedra (SFT) are examined using the phenomenon of the temporal fluctuation of the size of small SFT, below 3 nm in edge length, by the temporal and spatial fluctuation of point defect reactions under high-energy electron irradiation. Electron irradiation of pure copper and simultaneous observation is performed with a high-voltage electron microscope. The behaviour of SFT under electron irradiation is recorded with a videotape recorder through a camera tube. By the analysis of time series of the size of each SFT, support is given to the mechanism that SFT grow or shrink by the nucleation of ledges and their propagation on the SFT faces. The absorption rate of each type of point defect by SFT is also evaluated by Brownian-type analysis. The absorption rate increases with the rise in temperature. The total cross-section for the capture of point defects by a SFT is estimated to be about 500 for each type of point defect.
Keywords copper, electron microscopy, fluctuation, point defect, radiation effect, stacking fault tetrahedron