Influence of the elastic strain energy on the nucleation of {Omega} phase in Al-Cu-Mg(-Ag) alloys
- Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Materials Science and Engineering
The shape and orientation of the minimum elastic strain energy is found to occur at disc shape on {l_brace}001{r_brace} planes in the cases of Cu-Al clusters as well as of pure Cu clusters. The Mg-rich clusters, on the other hand, give rise to the minimum strain energy condition at disc shape on {l_brace}111{r_brace} planes, largely due to the difference of the anisotropy factor. The formation of thin Mg (or Mg-Cu) clusters of disc shape on {l_brace}111{r_brace} planes is believed to be mainly responsible for the precipitation of {Omega} phase in Al-Cu-Mg(-Ag) alloys. This prediction is confirmed by a recent result of atom probe study of Ringer et al. The presence of Ag has an effect to accelerate the nucleation kinetics of Mg clusters by reducing their elastic strain energy during the nucleation.
- OSTI ID:
- 99256
- Journal Information:
- Scripta Metallurgica et Materialia, Journal Name: Scripta Metallurgica et Materialia Journal Issue: 2 Vol. 33; ISSN 0956-716X; ISSN SCRMEX
- Country of Publication:
- United States
- Language:
- English
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