Fabrication of Micro-featured Shapes of Alumina Ceramics

Abstract

The present paper discusses the investigation carried out on three casting methods employed for the fabrication of micro featured shapes of alumina ceramics. The study involves the colloidal processing of submicron sized alumina powder in deionised water as well as in a mixture of deionised water and monomer followed by various casting techniques namely slip casting, gel casting and mouldless casting. While the slip casting method uses porous moulds and gel casting uses non porous moulds, the novel mouldless casting method does not use any mould. The experimental tools used for optimization of the slurry for the different casting techniques and the results obtained are presented. The cast products were sintered in the temperature range of 1400°C to 1600°C and were characterized for density, porosity, microstructure development and mechanical properties. The viability of three methods for producing micro features in the range of 50 to 500μm both on the surface as well as internally in the 3 dimensional structures have been demonstrated.