The steel-based surface composites were fabricated with the carbon steel ZG310-570 being selected as matrix and high carbon ferrochrome as cast-penetrated agent by conventional cast-infiltrating process combined with the thermite reaction.Influences of aluminum content in thermite reaction on the microstructures

thickness and properties of cast-infiltration layer were investigated.The results show that the interfacial bonding exhibits metallurgical fusion between cast-infiltration layer and the matrix

and the cast-infiltration composites mainly consist of M7C3

Cr7C3 and Al2O3 phase in the cast-infiltration layer containing aluminum powder

and the thickness and wear resistance of the composite layer are increased with the increase of aluminum content when the aluminum content is less than 2%

the pouring temperature is 1 650 ℃

and the preforms（thickness 10 mm）are embedded in the middle-bottom location of the mold wall.The cast-infiltration layer containing 2%Al exhibits desirable properties

where the thickness reaches to 15 mm

and the wear resistance is approximately 6.65 times higher than that of the matrix.