Microstructure of Nanocrystalline Ceramics

Abstract

ABSTRACTThe microstructure of nanocrystalline (n-) TiO2 was studied as a function of sintering temperature up to 1273 K. Grain growth was monitored using x-ray diffraction and scanning electron microscopy. Measurements of density and permeability of He and Ar were also conducted. The specific surface area and the total pore volume were determined quantitatively using the nitrogen adsorption method. These measurements revealed that highly compacted n-TiO2 had green body densities as high as 75 % of bulk density and that sintering occurred at much lower temperatures than in conventional powder. Densification proceeded by loss of the small pores first. The possibilities of achieving high densities with limited grain growth will be discussed.