Densification behavior of nanocrystalline titania powder under cold compaction

Abstract

Densification behavior of nanocrystalline titania powder was investigated under cold compaction. Experimental data were obtained from triaxial compression with various loading conditions. Lee and Kim proposed the Cap model by employing the parameters involved in the yield function of sintered metal powder and volumetric strain evolution under cold isostatic pressing. The parameters in the Drucker/Prager Cap model and the proposed Cap model were obtained from experimental data under triaxial compression. Finite element results from the models were compared with experimental data for densification behavior of nanocrystalline ceramic powder under cold isostatic pressing and die compaction. The proposed model and the Drucker/Prager Cap model agreed well with experimental data under cold compaction. Finite element results and experimental data also, show that relative density distribution of nanocrystalline ceramic powder compacts is nonuniform compared to the conventional micron powder compacts at the same averaged relative density. (c) 2007 Elsevier B.V. All rights reserved.