Nano-sized SiC particles reinforced aluminum matrix composites were fabricated by mechanical stirring and high-intensity ultrasonic method

and mechanical properties and microstructure of the prepared composites were investigated.The results reveal that compared with those of ADC matrix alloy

the tensile strength

elastic modulus

reduction of area and hardness of the composites are improved by 23%

43%

160% and by 7.4%

respectively

with 2.0% SiC reinforcement in weight percent.The tensile fracture morphology and distribution of SiC particles in the composites were observed by SEM（scanning electron microscope）.It is found that SiC particle is uniformly and dispersedly distributed in the matrix alloy with absence of large cluster.Meanwhile

uniform distribution of nano-sized SiC particle plays the role in inhibiting or restraining the creation and propagation of crack in the composites.