Back to Search
Start Over
Crystal orientation dependence of surface modification in molybdenum mirror irradiated with helium ions.
- Source :
-
Journal of Nuclear Materials . Dec2014, Vol. 455 Issue 1-3, p297-300. 4p. - Publication Year :
- 2014
-
Abstract
- The crystal orientation dependence on a surface damage in molybdenum mirror has been investigated under the irradiation with 3 keV helium ions to a fluence of 10 22 ions/m 2 . A strong correlation between the surface roughening and the grain orientation was confirmed from SEM–EBSD analysis. It was found that significant surface roughening including crater-like depressions is formed on the grain surfaces with crystalline planes close to (1 0 0), while relatively smooth surface remains on grains with the other directions. In contrast, the reflectivity measurement of the single crystal molybdenum with a spectroscopic ellipsometry showed smaller reduction in (1 0 0) sample than in (1 1 0) and (1 1 1) samples. The smallest helium desorption in (1 0 0) sample was also detected with thermal desorption spectroscopy in comparison with them in (1 1 0) and (1 1 1) samples, which indicates (1 1 0) and (1 1 1) samples include the large amount of defects acting as effective trapping site for He atoms. A cross-sectional TEM observation actually showed a relatively large bubbles at sub-surface regions of (1 1 0) sample. These results indicate that the optical reflectivity should be affected by not only a top surface profile but also internal radiation damages such as high density of helium bubbles. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 00223115
- Volume :
- 455
- Issue :
- 1-3
- Database :
- Academic Search Index
- Journal :
- Journal of Nuclear Materials
- Publication Type :
- Academic Journal
- Accession number :
- 99790763
- Full Text :
- https://doi.org/10.1016/j.jnucmat.2014.06.030