Abstract
In this research, effects of the multi-walled carbon nanotubes (MWCNTs) addition on mechanical properties and microstructures of spark plasma-sintered MWCNT/alumina composites were investigated by using four types of MWCNTs that were annealed at different temperatures. The annealing temperatures were 1200, 1800, 2200 and 2600℃. Experimental results showed that bending strength of the composites was increased up to 1800℃, and they were decreased gradually with increasing annealing temperature of MWCNTs. According to the fracture surface observation, dispersibility of the MWCNTs tended to decrease with increasing the annealing temperature of the MWCNTs, and fracture toughness of the composites corresponded to the dispersibility of the MWCNTs. The present study implies that the effectiveness of the use of MWCNTs having a higher load carrying capacity and dispersibility for preparation of stronger and tougher ceramic composites.