Chemo-Rheological Behavior of Aqueous Titanium Carbide Suspension and Evaluation of the Gelcasted Green Body Properties

摘要

Gel-casting is an advanced colloidal processing method for fabricating ceramic green parts. In this project acrylamide-based monomers were used as a gelcasting system. The effects of tetramethylammonium hydroxide and polyethylenimine dispersants on the premix solution containing titanium carbide powder have been studied via observation of the zeta potential and rheological behavior. The effect of various parameters on the gelation time and viscosity of solution and flexural strength and the shrinkage rate of titanium carbide green body were investigated. The results presented that the order of dispersion capacity of the tetramethylammonium hydroxide dispersant was better than the polyethylenimine dispersants. The results showed that the gelation time decreased and viscosity increased with increasing the monomer content, solid loading, initiator amount and temperature. The highest bending strength (39 MPa) was obtained for the samples containing 25 wt.% monomer content and 50% solid loading.