Abstract: The mechanisms and kinetics of the initial period of sintering of ZrO 2 nanometer powder studied by measuring the sintering shrinkage of powder compacts are divided into different stages. In the first stage, the sintering kinetic is written as Δ L/L 0∝t ,and the boundary diffusional creep,due to the boundary diffusion and the rearrangement of primary particles in compact, is the main factor affecting the sintering and sintering densification. The microstructure of the compact is characterized by the existence of a high coordination number of small pores. In the second stage, the sintering of compact is controlled by the grain boundary diffusion. An equation of the sintering kinetic of this stage can be expressed as Δ L/L 0∝t 1/3 .

Key words: ZrO2, nanometer powder, sintering