EFFECT OF PARTICLE CONTENT ON GRAN GROWTH AND PROPERTIES OF AL-ALONANOCOMPOSITES PRODUCED BY MECHANICAL ALLOYNG AND HOT-PRESSING

In this study Al-Al2O3 nanocomposite powders containing 5, 10 and 15 Wt% of nanopowder were produced by mechanical alloying. For comparing, Al-Al2O3 composite powder containing 5Wt:6 of micrometric Al2O, was also produced. The powder was then hot-pressed in a mold to produce 4.2X 1.2X 1.2cm bulked parts. The effect of Al2O3 content on grain growth, density and hardness of bulked composite was discussed and microstructures were investigated by optical and scanning electron microscopy. The results revealed that when nanometric particles were used instead of micrometric particles the grain growth was reduced, while the increase of particle weight percentage did not affect the grain growth.

Keywords:

Nanocomposite , Al2O3 , Powder metallurgy , Mechanical alloying , Hot-Pressing