Journal
ACTA MATERIALIA
Volume 61, Issue 15, Pages 5636-5645Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.actamat.2013.05.044
Keywords
Cast aluminium; Grain refinement; Peritectic; Edge-to-edge matching model
Funding
- Australian Research Council
- China Scholarship Council
Ask authors/readers for more resources
The mechanism underlying the grain refinement of cast aluminium by zirconium has been studied through examination of a range of Al alloys with increasing Zr contents. Pro-peritectic Al3Zr particles are reproducibly identified at or near the grain centres in grain-refined alloy samples based on the observations of optical microscopy, scanning electron microscopy and X-ray diffraction. From the crystallographic study using the edge-to-edge matching model, electron backscatter diffraction and transmission electron microscopy, it is substantiated that the Al3Zr particles are highly potent nucleants for Al. In addition, the effects of Al3Zr particle size and distribution on grain refinement has also been investigated. It has been found that the active Al3Zr particles are bigger than previously reported other types of active particles, such as TiB2 for heterogeneous nucleation in Al alloys. Considering the low growth restriction effect of Zr in Al (the maximum Q-value of Zr in Al is 1.0 K), it is suggested that the significant grain refinement of Al resulting from the addition of Zr can be mainly attributed to the heterogeneous nucleation facilitated by the in situ formed Al3Zr particles. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available