Nano-sized SiC particles reinforced magnesium matrix composites（n-SiCp/AZ91D） were fabricated by mechanical stirring combining with high intensity ultrasonic dispersion processing.Influences of n-SiCp content and temperature on the friction and wear behavior of the composites prepared were investigated by a ball-on-disc testing.The results show that the resistant friction and wear behavior of the nano-composites is improved greatly with nano-SiC particle

and with the increase of n-SiCp content

it is gradually enhanced.Temperature plays important roles in controlling resistant friction and wear behavior of the nano-composites prepared.From room temperature to 300 ℃

both the AZ91D alloy and its composites undergo mild-to-severe wear regime change.The transition temperature of the nano-composites prepared from mild to sever wear is increased by 50 ℃

compared with that of AZ91D matrix.In addition the nano-composites exhibit better high-temperature resistant friction and wear bahvior.