Published online by Cambridge University Press: 31 January 2011
Mullite ceramics with controlled microstructure in terms of residual glassy phase and density were produced from diphasic silica/boehmite sols using pressure filtration, die-pressing, and extrusion techniques. The effect of the compaction process on the green and sintered densities and on the final mullite microstructure was investigated. It is shown that glassy-phase-free mullite with high green and sintered densities can be produced from engineered diphasic colloidal suspensions using pressure filtration. The results show that the green body formation technique strongly determines the final sintered density, but it has no effect on the final phase composition of diphasic sol-derived sintered mullites.