Abstract
The Jominy end quench test has been adopted to investigate the effect of trace scandium on the quench sensitivity of Al-7Si-0.6 Mg alloys. The results show that at a lower quenching rate, the preferred precipitation of the Al3Sc phase inhibits the formation of a β′-Mg2Si phase, promoting the nucleation of finely dispersed metastable Mg2Si precipitates in the subsequent aging treatment. The quench sensitivity of the Al-7Si-0.6 Mg alloy was effectively improved by more than 60%. Rapid quenching rates can cause the Al matrix of the alloy to be in a supersaturated state, resulting in enhanced mechanical properties after aging treatment. In contrast, slow quenching rates precipitate the relatively coarse β′-Mg2Si phase and also produce a precipitate free zone during the quenching process, thereby diminishing the mechanical properties of the alloy after the aging treatment, so that the Al-7Si-0.6 Mg alloy possesses higher quench sensitivity.
Original language | English |
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Pages (from-to) | 340-342 |
Number of pages | 3 |
Journal | Materials Letters |
Volume | 161 |
DOIs | |
State | Published - 15 Dec 2015 |
Keywords
- Al<inf>3</inf>Sc
- Cast
- Metals and alloys
- Microstructure
- Scandium