Wear properties of mechanically alloyed and hot-pressed Al۲O۳-AlNanocomposite

In this study, Al matrix composite (AMC) powders containing ۱۰ wt% of nano-size Al۲O۳as reinforcing particles were mechanically alloyed by high energy planetary ball mill.Microstructure of produced composite powder at different milling times was investigatedby X-ray Diffraction techniques and scanning electron microscope. A uniform distributionof the Al۲O۳ reinforcement in the Al matrix was obtained after ۱۵ hours milling time at۲۵۰ rpm. The powders were then hot pressed at ۴۰۰°C for ۴۰ minutes by uniaxial pressingat ۶۰۰ MPa. The results revealed the hardness and wear resistance of the compositeincrease by increasing of milling time, whereas relative density and grain size decrease.Wear test was carried out and resulted weight losses for various milling times at ۲۰N werestudied

Keywords:

nanocomposite , aluminium , alumina , wear , mechanical alloying.