Preparation of Sintered Glass-ceramics: A Comparison of Different Binders

摘要

With the rapid increase of solid wastes and the decrease in natural resources, the reutilization of the wastes has become an urgent need. Sintered glass-ceramics with gehlenite and anorthite as main crystalline phases have been prepared with glass powder made from a waste water flocculate. In this work, different binders, including diluted water glass, polyvinyl alcohol (PVA) solution and kaolin were added to form green bodies for making sintered glasses ceramics. Effects of the binders on the sintering shrinkage of the green bodies, the crystallization of the glass powder upon sintering and the microstructure of the sintered glass-ceramics have been investigated. The results indicate that the kaolin benefits the reduction of the shrinkage and may have negative effect on the formation of glass-ceramics with fine grained crystallites. In contrast, PVA and water glass solutions as binders lead to larger shrinkage values and glass-ceramics with well distributed smaller crystallites.