The as-extruded Mg-11 Li-3 Al-xZr（x=0

0.1）alloy was treated by solid solution at different temperatures.The microstructure and mechanical properties of the alloys after solid solution treatments were investigated by OM

XRD

SEM

hardness and tensile test.The results reveal that the as-extruded Mg-11 Li-3 Al alloy is mainly composed ofβ-Li phase

α-Mg phase

θ-MgLi

2

Al phase and AlLi phase

and these phases are redissolved in theβ-Li matrix after solid solution treatment at 450℃

and the grain size is coarsened.The Mg-11 Li-3 Al-0.1 Zr alloy is mainly also composed ofβ-Li phase

α-Mg phase

θ-MgLi

2

Al phase

AlLi phase with absence of new phase generation

and theβ-Li single-phase alloy can be generated by solid solution treatment also at 450℃

meanwhile

the grain size cann’t be changed obviously

however

the thermodynamic stability is improved.With the increase of solution temperature

the hardness of as-extruded Mg-11 Li-3 Al-xZralloy（x=0

0.1）is increased

and reaches the peak value at 400～450℃.Meanwhile

the yield strength and tensile strength of the alloy are increased significantly

while the elongation is decreased.