Microstructure and Properties of Mg-10% Al-(0 ∼ 3%) Di Alloys

The effects of didymium (Nd: Pr = 3:1) on the microstructure and mechanical properties of Mg-10% Al alloy were studied with the additions of 0 ∼ 3% Di. The small block-like Al2(Nd, Pr) phase appears in 1% Di alloy, the blocklike Al2(Nd, Pr) and needle-like Al11(Nd, Pr)3 phases appear synchronously in 2% Di and 3% Di alloys, while the network of (Mg17Al12) β phase is broken up. The tensile properties can be improved with the addition of didymium. When the addition of didymium in Mg-10% Al alloy reaches 2%, the alloy exhibits the best combination of strength and ductility, but the strength and ductility drop at the addition of 3% Di due to the obvious increase of the size and quantity of the needle-like Al11(Nd, Pr)3 phase.