The lamellar-interpenetrated gradient SiC/Al-Si-Mg composites with 20% SiC content（in volume fraction）were prepared by directional freeze casting combined with squeeze infiltration process.The microstructure and element distribution in composites

interface between Al-Si-Mg and SiC were investigated by scanning electron microscope（SEM）

energy dispersive spectroscopy（EDS）and X-ray diffraction（XRD）.The results reveal that liquid Al-Si-Mg alloy is completely infiltrated in the lamellar SiC preform prepared by directional freeze casting process and the interface of Al-Si-Mg and SiC in composite is well bonded.The gradient lamellar structure of SiC preform is well preserved in the composites.The SiO

2

film is generated on the surface of SiC particles after sintering at 1 300℃

and the MgAl

2

O

4

phase is formed in the infiltration process

which improves the wettability and interface bonding between the matrix phase and the reinforced phase.