Mg/Al composite plates were fabricated by liquid-solid cast rolling technology

which were annealed treatment subsequently.The effects of annealing temperature on the relationship between microstructure and mechanical properties of the composite plates were analyzed.The results reveal that the interfacial transition zone of Mg/Al composite plates is divided into three regions

region Ⅰ adjacent to AZ31B forming Mg transition region(δ-Mg and Mg

17

Al

12

)

region Ⅱ close to A356 forming Al transition region（α-Al and Al

3

Mg

2

）

and the diffusion interfacial middle region Ⅲ (Mg

17

Al

12

、Mg

2

Si and Al

3

Mg

2

).The width of Al transition region is more than that of Mg transition zone.The microhardness of the interfacial transition zone is obviously higher than those of bilateral alloys.When the annealing temperature is or lower than 250 ℃

absence of new intermetallic compounds can be observed in the interfacial transition zone.When annealing temperature is higher than 250℃

thickness of the interfacial transition zone is grown in form of exponent with the increase of annealing temperature.After annealing at 250 ℃ for 180 min

the tensile strength

yield strength and elongation of the composite plates reach 188 MPa

148 MPa and 10.1%

respectively

and the comprehensive mechanical properties present desirable.