Rapid consolidation of nanocrystalline Al_2O_3 reinforced Cr composite from mechanically alloyed powders by pulsed current activated sintering

摘要

Nanopowders of Cr and Al_2O_3 was fabricated from CrO_3 and 2Al by high energy ball milling. Dense nanocrystalline Cr-Al_2O_3 composite was consolidated by pulsed current activated sintering (PCAS) method within 1 min from mechanically alloyed powders. Highly dense Cr-Al_2O_3 with relative density of up to 99% was produced under simultaneous application of a 80 MPa pressure and the pulsed current. The average grain size and mechanical properties of the composite were investigated.