Pulse Electric Current Sintering of Al2O3/Cu Nanocomposites

Abstract

The nanocomposite powder of Al2O3/Cu was prepared by mechanical alloying of the elemental powders of Al2O3 and Cu. The characteristics of the powder were analyzed by X-ray diffraction analysis and scanning eletron microscopy. The nanocomposite powder was sintered with use of PECS(Pulse Electric Current Sintering) facility. Recently, many reports have been given that PECS is very effective for suppressing a grain growth during densification, which might be resulted from the shorter holding time at lower sintering temperature than in conventional sintering method. Sintering was carried out under various conditions in which the following factors was changed : temperature, holding time, atmosphere(vacuum and Ar gas), pulse rate(number of on/off per minute), and heating/cooling rate. On sintered parts crystallite size, microstructure, mechanical properties such as hardness and fracture toughness were also investigated.