The densification and morphology of cordierite-based glass-ceramics

In this study, five different proportion of a borosilicate glass (from 30 t o 70 wt%) were added to stoichiometric cordierite to improve the densificat ion behaviour of cordierite-based glass-ceramics. The phase and microstruct ural evolution of the samples were characterised by DTA and SEM. The result s show that glass content plays an important role in the sintering of cordi erite-based glass-ceramics. The sintered density increases as the glass con tent increases at low temperature (950 degreesC). At high temperatures, the sintered density passes through a maximum value when the glass content is about 60 wt.%. followed by a decrease as the glass content further increase s. DTA results show that densification is a non-reactive liquid phase sinte ring process. The microstructural evolution of the samples is in good agree ment with the measurements of sintered densities. At the lower glass conten t, the sample shows more pores and a non-uniform pore size distribution. Wi th the glass content increasing, the pore size becomes more uniform and sin tered density increases. (C) 2001 Elsevier Science B.V. All rights reserved .