LIQUID-PHASE SINTERING IN THE GLASS-CORDIERITE SYSTEM - PARTICLE-SIZE EFFECT

The effect of particle sizes of glass and ceramic filler on the densification kinetics of glass-filled ceramics has been studied using borosilicate glass-cordierite as the model system. Within the particle size range investigated, the densification is found to be significantly enhanced by increasing the cordierite size, reducing the glass size and increasing the green density. These results are attributed to both the increased driving force of densification by reducing the glass particle size and the decreased glass redistribution distance by either increasing the green density of compacts or increasing the particle size ratio between the cordierite and glass powders. In addition, a large cordierite-to-glass size ratio gives a dense, uniform microstructure of sintered body as a result of forming a homogeneous close packing of the low-melting glass phase around the refractory cordierite particles.