Gelcasting of BeO

Abstract:

Aqueous gel-casting of beryllia using polyelectrolyte NH₄PAA as a dispersant has been investigated. The effects of the dispersant amount, pH values on the surface properties of BeO powders in aqueous solvent were studied and high solids loading BeO suspension (45 vol.%) was developed. A premix solution containing 15-20 wt.% of AM monomer can provide enough mechanical strength for the green body obtained from 45 vol.% BeO suspension. SEM photography indicates that BeO ceramics with homogeneous microstructure can be fabricated. The thermal conductivity of sintered green body is 182.1±10 W/(m.K). Gelcasting is a suitable process to form BeO ceramic parts.

• Periodical: Applied Mechanics and Materials (Volumes 184-185)
• Pages: 992-1000
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.184-185.992
• Online since: June 2012
• Authors: Wei Shi
• Keywords: BeO, Dispersion, Gelcasting, Suspension, Thermal Conductivity (TC)

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