Abstract
Well-dispersed multi-walled carbon nanotubes (CNTs) reinforced Al2O3 nanocomposites were successfully fabricated by hot-pressing. The resulting promising improvements in fracture toughness, by 94% and 65% with 2 and 5 wt.% CNTs addition respectively, compared with monolithic Al2O3, were attributed to the good dispersion of CNTs within the matrix, crack-bridging by CNTs and strong interfacial connections between the CNTs and the matrix. The interfacial phase characteristics between CNTs and Al2O3 were investigated via combined techniques. It is believed that a possible aluminium oxy-carbide as the primary interfacial phase was produced via a localized carbothermal reduction process. This interface phase presumably has good chemical compatibility and strong connections with both CNTs and the matrix and led nanocomposites to higher fracture toughness. (C) 2010 Elsevier Ltd. All rights reserved.