The interfacial microstructure and morphology of Al/LZ91/Al alloy laminated composite plate were observed by optical microscopy（OM）and scanning electron microscopy（SEM）

and effects of different temperature and holding time of annealing on interfacial diffusion and tensile properties of the composite plate were investigated.Meanwhile

the diffusion equation was established.The results show that recovery and recrystallization can be observed with increasing in annealing temperature or annealing time

and the microstructure of inner layer LZ91 magnesium alloy is composed of uniform and equiaxed grains.After annealing treatment

diffusion of Mg

Al and other elements occurs

and interface consists ofα-Mg+β-Li phase

Mg17Al12 phase

Al3Mg2phase andα-Al phase.After annealing treatment at 300℃for 1h

tensile strength and elongation of plate reach 130 MPa and 15.8%

respectively.