Gelcasting is an attractive novel ceramic forming process for making high-quality, complex-shaped ceramic parts. The idea of this method is based on a slurry made from ceramic powder and water based monomer solutions is poured into a mold. The ceramic slurry consists of a ceramic powder, organic or inorganic solvent, organic monomer and free radical initiator. Water is a preferred solvent. At appropriate conditions is possible to start the polymerization in the ceramic slurry.
The general aim of research is looking for new water-soluble low toxic monomers. The aqueous monomer solution provides a low-viscosity vehicle that is combined with ceramic powder and appropriate dispersants to form a highly fluid slurry. That is why in our research we use only water-soluble organic monomers, for example 2-hydroxyethyl acrylate.
The choice of organic monomer and initiator system depends on several factors just like gel strength, wet and dry strength of ceramic sample, reactivity.
The ceramic slurry was based on the alumina powder. Gelcasting is very close to the traditional ceramic processing. In this process we can use the same dispersants as are normally used for slip casting; no special molding machines or presses are needed. We use standard mixing equipment such as ball mills for slurry preparation in the gelcasting process.
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