EFFECT OF PARTICLE-SIZE ON THE SINTERING OF LI2O-AL2O3-4SIO(4)-BOROSILICATE GLASS COMPOSITES

The effect of spodumene particle-size on the sintering of spodumene-bo rosilicate glass composites was investigated. The results can be expla ined by a particle-size dependence of the extent of reaction between s podumene and glass. For samples fabricated with fine spodumene particl es (1.5-3 mu m), a reactive liquid-phase sintering behaviour was obser ved. Smaller particle size resulted in a higher sintered density and c oarser microstructure. For samples fabricated with coarse spodumene pa rticles (3-7 mu m), a non-reactive liquid-phase sintering behaviour wa s observed when a high-viscosity glass, a lower initial glass content, and a lower sintering temperature were used. A larger particle size r esulted in a higher sintered density and coarser microstructure. If a low sintering temperature or a coarse (e.g., 7 mu m) particle size wer e used, the dissolution of the glass into spodumene was reduced which resulted in an increased amount of glass crystallization.