Abstract
Systematic experiments of 1 MeV electron irradiation were made on Cu-based binary alloys above 300 K using a high-voltage electron microscope in order to study the effects of solute atoms on defect structure development. The solute elements examined were Si (+5.08%), Ge (+27.77%) and Sn (+83.40%), the volume size factors of which are given in parentheses; the amounts of these were 0.05, 0.3 and 2 at.% respectively. Interstitial-type dislocation loops and stacking-fault tetrahedra (SFTs) were formed in pure Cu and all the alloys. In pure Cu, the temperature dependence of the loop number density had a ‘down peak’ (i.e. loops hardly formed) around 373 K; below this temperature the majority of the loops shrank and disappeared during irradiation, while all the loops grew larger above it; and SFTs were unstable and repeated the formation and disappearance. In the alloys, the loop number density decreased monotonically with increasing temperature (no down peak was observed); loop formation was greatly enhanced except for complete suppression above certain temperatures in Cu-Ge and Cu-Sn alloys; and stable SFTs formed up to higher temperatures. The mechanisms for these effects were proposed, taking into account the trapping of point defects by solute atoms, the radiation-induced segregation of solute elements, and the bias effect on point-defect absorption at defect clusters owing to the segregated solute elements.
Original language | English |
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Pages (from-to) | 2567-2590 |
Number of pages | 24 |
Journal | Philosophical Magazine A: Physics of Condensed Matter, Structure, Defects and Mechanical Properties |
Volume | 80 |
Issue number | 11 |
DOIs | |
Publication status | Published - 2000 Jan 1 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Materials Science(all)
- Condensed Matter Physics
- Physics and Astronomy (miscellaneous)
- Metals and Alloys