Abstract
The microstructure and hardness of as-cast Mg-4.2Zn-0.8Y-xGd (at.%, x = 0, 0.5, 1) alloys were investigated. It has been found that MgZn3Y (H phase) and Mg3Zn3Y2 (W phase) are the main precipitates in the as-cast alloy without Gd. A long-period stacking ordered (LPSO) phase formed upon adding Gd, indicating that the Gd addition enhanced the stability of the LPSO phase. The Gd addition also increased the overall amount of the alloying elements; thus the grain size decreased and the volume fraction of the secondary phases increased resulting in increased hardness of the as-cast alloys. The Y and Gd partition between different phases was investigated. The results show no clear preference between Y and Gd when forming the matrix and the secondary phases, though small fluctuations exist.
Original language | English |
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Pages (from-to) | 455-460 |
Journal | Journal of Alloys and Compounds |
Volume | 661 |
Early online date | 6 Dec 2015 |
DOIs | |
Publication status | Published - 15 Mar 2016 |
Keywords
- Magnesium alloys
- Gadolinium addition
- Long period stacking ordered (LPSO) phase
- Quasi-crystalline phase