Effect of Ti on microstructure and properties of electromagnetic stirred Al-18wt.%Mg 2 Si alloy

By adding different amounts of Ti into the electromagnetic stirred Al-18wt.%Mg 2 Si alloy, the effect of Ti element on the microstructure and mechanical properties of the alloy was studied. The experimental results show that the microstructure is refined after modification with Ti, which is related to the heterogeneous nucleation of TiAl 3 particles on the α-Al matrix. With the increase of Ti content and holding time after stirring, the primary Mg 2 Si phase is refined firstly and then coarsened, and correspondingly, the mechanical properties of the alloy show a trend of increasing at first and then decreasing. When the addition of Ti is 0.5wt.% and the holding time is about 20 min, the refinement effect of primary Mg 2 Si phase is the most significant and the mechanical properties of the alloy are optimal.