Gelcasting of alumina suspension using gellan gum as gelling agent

As one of the excellent colloidal ceramic forming methods for fabricating complex shaped ceramic components, gelcasting has been extensively investigated in the past two decades. In this article, a novel nontoxic system for gelcasting of ceramics was investigated using gellan gum as gelling agent. The rheological and gelling properties of gellan gum solutions with different types of cations and different concentrations of divalent magnesium ions were studied. Influences of concentration of gellan gum and solid loading of alumina suspension on the rheological properties and gelling properties of alumina suspension were investigated. The rheological properties of concentrated alumina suspension mixing with gellan gum and magnesium chloride were evaluated. Dense ceramics prepared by gellan gum gelation showed homogeneous microstructure and good mechanical properties.