Effects of combined additions of Li and Al–5Ti–1B on the mechanical anisotropy of AZ31 magnesium alloy

AZ31 magnesium alloys with Li and/or Al–5Ti–1B were cast and extruded to sheets with a thickness of 2 mm. The microstructure, tensile properties and anisotropy behavior of these alloys were investigated. The results showed that the grain sizes of AZ31 alloys were reduced by combined addition of Li and Al–5Ti–1B both in the as-cast and the extruded conditions. AZ31–1Li–0.3(Al–5Ti–1B) Alloy was found to exhibit better tensile properties and improved anisotropy with a modest strain hardening exponent n ∼ 0.28. This was explained via the texture evolution and the refined microstructure. Li addition decreased the axial ratio (c/a) of Mg and the addition of Al–5Ti–1B refined the grain size through dynamic crystallization during extrusion.