Materials Science Forum, Vol.475-479, 1317-1320, 2005
Study on elimination of surface-exfoliation and crack of ZrO2 green body of gelcasting with water-solubility macromolecule
Ceramic gelcasting has to be performed in nitrogen to avoid surface-exfoliation and crack of the green body. The rapid drying of gelled bodies can cause nonuniform shrinkage. Non-uniform drying in various regions due to the solvent gradient, induces structural and residual stresses which cause defects, such as cracking, warpage and the other malformations. These malformations can be minimized or eliminated via adding a proper amount of water-soluble polymer polyethylene glycol(PEG). This study concentrates attention on dispersion, rheological property and gelation behavior in the new system, The flexural strength and microstructure of ZrO2 green bodies were measured and observed.