Microstructure and hardness dependence of the pressure of nano-crystalline aluminum

Nano-crystalline aluminum was synthesized by a new method of ball-milling technique from ingots of 99.8 wt.% Al. The effect of pressure on the microstructure and mechanical properties of compacted ball-milled aluminum was investigated in a pressure range up to 300 Pa. The dislocation density and micro-hardness of our specimens increase by increasing the pressure. The best fit line describes the H–P relationship dependence of micro-hardness (HV0.010) on the grain size for compacted aluminum obeys the following formula:HV0.010=35.42〈D〉−1/2+245.02(kgmm−2)