The Effect of Mg on the Wetting Behavior of SiC-Al System

The wetting behavior of SiC by molten Al and Al-Mg alloys using the sessile-drop testing equipment was investigated. The results showed that Mg has a remarkable influence on the wettability and reaction in the Al/SiC system. The contact angle between SiC substrate and molten Al-Mg alloys decreased more quickly with increasing of Mg content. The transition temperature from non-wetting to wetting dropped with increasing of Mg content, suggesting that the addition of Mg does promote the wettability of SiC by molten Al. The role of the Mg addition on the wetting was presumably attributed to its deoxidation as well as the inhibition of the interfacial reaction between Al and SiC.