Cu-SiC

p

/AZ91Dcomposites were prepared under normal conditions and microgravity magnetic fields

and the structure and phase composition of the composites were analyzed.Microstructure’s formation mechanism and anti-friction properties were also analyzed.The results show that the composites prepared under normal conditions are mainly composed ofα-Mg

β-Mg

17

Al

12

and Mg

2

Si

and the grain size is the smaller than that of AZ91D

however its homogeneity is low.Under the simulated microgravity conditions

Cu-SiC

p

/AZ91Dcomposites are mainly composed ofα-Mg and Mg

2

Si phases

and the microstructure homogeneity is improved significantly with the further refinement of the grain

and microhardness is increased to about HV

4.9

80.46.The frictional wear test shows that the Cu-SiC

p

/AZ91Dcomposites prepared by simulated microgravity conditions have the lower friction coefficient and wear rate.