The Effect of Rheological Parameters on the Behavior of Silicon Nitride-Starch Slurry Used in Gelcasting Porous Silicon Nitride

Authors

Iran University of Science and Technology, School of Metallurgy and Materials Engineering.

Abstract

In this research, the rheological behavior and stability of suspensions containing Si3N4, Al2O3, Y2O3 and starch were investigated in order to use them in the starch consolidation casting of porous silicon nitride. Dolapix CE64 was used as the dispersant. Then, the effect of some parameters such as Si3N4 surface oxidation, dispersant content, solid loading and starch content on the viscosity and rheological behavior of Si3N4-starch slurry was determined. Surface oxidation of Si3N4 powder at 800°C for 2 hours reduced the viscosity of the slurry, effectively. The best dispersant content was 0.4 wt. %, relative to ceramic powders. Slurries containing 30 to 40 vol. % and 7.5 to 25 vol. % starch, relative to total solid loading, had the suitable viscosity and the sufficient stability for casting by the starch consolidation method.

Keywords

References

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Journal of Advanced Materials in Engineering (Esteghlal)
Volume 37, Issue 4
March 2019
Pages 13-23

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