To further improve the surface quality and enhance the corrosion resistance of Zn-6Al-3Mg (ZAM) alloy, the refinement effects of Ti or Ti/B additions on Al dendrites in ZAM alloy were investigated. The results showed that the Al dendrites in ZAM alloy exhibited a standard secondary dendritic morphology. However, after adding Ti or Ti/B, the Al phase consisted of secondary dendrites, primary dendrites, and axial crystal morphologies. Both Ti and Ti/B additions effectively refined the Al dendrites, with ZAM-Ti/B alloy demonstrating superior refinement compared to ZAM-Ti alloy. Transmission electron microscope (TEM) results revealed that Ti and B additions induced the formation of new precipitated phases, namely TiAl$_3$ and TiB$_2$ in ZAM alloy. TiAl$_3$ appeared at the center of Al dendrites, while TiB$_2$ was typically surrounded by MgZn$_2$ phases. These precipitated phases effectively refined the Al dendrites in ZAM alloy.
DAI Jingge
,
LIU Yao
,
WU Guangxin
. Refinement effect of Ti/B on Al dendrites in Zn-6Al-3Mg alloy[J]. Journal of Shanghai University, 2025
, 31(4)
: 622
-631
.
DOI: 10.12066/j.issn.1007-2861.2684
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