Experimental study on strengthening of Mg–Li alloy by introducing long-period stacking ordered structure

18R long-period stacking ordered (LPSO) structure was introduced into Mg–Li alloys. For the investigated Mg–8Li–6Y–2Zn alloy, LPSO phase cannot be formed in the as-cast state as Mg–Y–Zn alloys, but it can be transformed from (Mg,Zn)24Y5 phase via heat treatment at 500 °C. Tensile test results indicate that the formation of 18R LPSO phase can effectively improve both the strength and plasticity of extruded Mg–8Li–6Y–2Zn alloy.