ABSTRACT
This chapter presents the basic material properties of pressureless sintering (PLS) processed multi-walled carbon nanotube/Al2O3 to elucidate the adequacy of PLS technique towards fabricating such nanocomposites having improved performance over pure Al2O3. Considering the structural integrity aspect of carbon nanotube (CNT) in sintered nanocomposites, morphological stability of present nanotubes during high temperature exposure in inert atmosphere was studied prior to the nanocomposite fabrication. The CNT clusters in high nanotube containing batches facilitated localized densification of the matrix phase that formed a segregated microstructure and eventually, produced the macroscopic cracks. Presence of clustered CNTs, porous microstructure and inadequate interface in this high CNT loaded nanocomposite resulted in much higher defect population. The chapter describes the sequential changes observed at the interface region of the studied nanocomposites as a function of sintering temperature. The observed discrepancy in the extent of toughness improvement in CNT/Al2O3 nanocomposites is quite common and yet ambiguous.
