Al-Mg-Cu-Sn-Ga alloys were prepared by smelting-casting method.The effects of indium addition on microstructure

mechanical properties and corrosion properties of the based alloys were investigated by means of X-ray diffraction（XRD）

scanning electronic microscope（SEM）

Vickers hardness

compression testing and immersion test.The results show that the alloys mainly consist of Al matrix phase

long strip Al

2

MgCu phase and skeleton Mg

2

Sn phase.In addition

a small amount of line-like Ga

5

Mg

2

phases are distributed the Al

2

MgCu phases.The indium element is segregated at the grain boundaries of the alloy matrix.When the content of indium element reaches to 1%

the hardness

compressive strength and degradation rate of the alloy reach 142HV

582 MPa and 4.7g/h

respectively.