A new particulate reinforced Al matrix composites was successfully prepared by the direct melt reaction in system of Al-Zr（CO

3

）

2

-KBF

4

.XRD and SEM analysis indicated that the formed fine ZrB

2

Al

2

O

3

and Al

3

Zr particulate with average grain size of 80～90 nm uniformly dispersed in the matrix.Tensile test showed that tensile strength

150.3 MPa

for 70.0 MPa of the Al matrix

raised by 92.7%

and yield strength

112.4 MPa

for the 42.0 MPa of the Al matrix

raised by 170.7%

of the composites remarkably increased with the increment of the reaction system addition.The elongation of the composites rises first and fall later.SEM observation reveals that although the ductile area is reduced with the increase of reaction system

the fracture mechanism is dominated.