Processing and fracture toughness of nano-sized Cu-dispersed Al2O3 composites

An optimum route for the fabrication of Al2O3/Cu nanocomposites with sound microstructure and enhanced fracture toughness was investigated. Cu-dispersed Al2O3 nanocomposites were obtained via hydrogen reduction and the pulse electric current sintering (PECS) of ball-milled Al2O3 and CuO powder mixtures. Microstructural observation of the reduced powder revealed that Cu particles of about 30 nm size homogeneously surrounded the Al2O3 powder. The nanocomposites, consolidated by PECS at 1250 degreesC for 5 min, exhibited full density and enhanced fracture toughness compared with monolithic Al2O3. (C) 2002 Elsevier Science B.V. All rights reserved.