Influence of Y and Nd on microstructure, texture and anisotropy of Mg-5Li-1Al alloy

Mg-5Li-1Al-0.5Nd/0.5Y alloys were prepared using a vacuum induction melting furnace. The microstructure and phase composition were investigated by optical microscopy, energy dispersive X-ray spectroscopy, scanning electron microscopy and X-ray diffraction. The mechanical properties of alloys were measured with tensile tester. The addition of rare earth element results in the formation of an Al-RE compound, such as Al2Nd and Al2Y, and it has a refining effect on the microstructure of the alloy. Dynamic recrystallization that happens during the rolling refines the grains of the alloy obviously. The addition of rare earth element activates the non-basal slip system, changes stacking fault energy of magnesium alloy, and weakens the basal texture because of PSN (particle stimulated nucleation) mechanism. The addition of Nd/Y enhances the strength anisotropy of the alloy, while it weakens the elongation anisotropy of the alloy.