Effect of green density on the subsequent densification and grain growth of ultrafine SnO₂ powder during isochronal sintering

An ultrafine powder of SnO₂ has been synthesized by a gas flow condensation method. The average particle size of the powder was about 40 nm. The effect of the green density on the subsequent densification and grain growth of the ultrafine SnO₂ during sintering has been studied. A loose green compact consolidated under 500 MPa (green MC) showed rapid densification as well as rapid grain growth at relatively low sintering temperatures. A dense green compact fabricated under 4.5 GPa (green GC) exhibited a slow increase in the density and almost no grain growth even at high sintering temperatures.