Sintering behavior of nanocrystalline zinc oxide powders

An increasing number of studies are aimed at the creation of oxide ceramics with grain sizes as low as possible because of their promising properties. In the present study nanocrystalline zinc oxide as starting material was prepared by electrodeposition under oxidizing conditions (EDOC). Green samples were formed by uniaxial pressing in a die and compacting in a cold isostatic press. The subsequent sintering was performed in air. The results for the above samples are compared with the behavior of zinc oxide produced by physical vapor synthesis and the indirect or French process. A final density of 90 % of theoretical density was obtained by using the powder produced electrochemically compared to 95 and 96 %, respectively, in the samples made of commercially available powders. Methods used for characterization of the compacts were porosimetry techniques, and scanning electron microscopy.