Densification of nanocrystalline ITO powders in fast firing: effect of specimen mass and sintering atmosphere

Preparing tin-doped indium oxide ceramic bulk via explosive consolidation and sintering of nanopowders

“…We obtained a uniformly sintered microstructure across the sample. The difference between our experiments and those in [14] may be as follows: in our experiments, the sample was highly consolidated and the shrinking rate was uniform over the sample cross section due to the residual stress, a large number of dislocations, and the twin grain structure forming after the instantaneous shock consolidation. The shock-consolidated sample should be fast sintered, because ITO will badly decompose under high temperatures with the time prolonged, which degrades ITO activation by the shock wave in the sintering process and yields a lower final density of the sintered bulk.…”

“…Kim et al [14] studied densification of nanocrystalline ITO powders with the fast firing sintering technique (the sample was placed into a furnace with a temperature equal to or slightly lower than the sintering temperature; hence, the sample reached the sintering temperature in a short time) and found that the sample could not completely shrink. The authors attributed the poor densification of the sample to faster outside densification, which resulted in formation of a hard shell preventing the inside of the sample shrinking as it normally would.…”

Synthesis and sintering of indium tin oxide nanoparticles by citrate-nitrate combustion method

“…The relative density value is 88.7% for the 1100C sintered sample, 91.7% for the 1200C sintered sample, 94.2% for the 1300C sintered specimen, and the highest value 97.3% was reached when sintered at 1400C. Kim et al [10]. obtained ITO nanoparticles by coprecipitation from starting materials In(NO 3 ) 3 and SnCl 4 .…”

“…Densification of In 2 O 3 ceramics is very difficult due to the rapid vaporization of In 2 O 3 and SnO 2 at temperatures above 1200C [6][7]. In order to suppress evaporation, ITO ceramics is usually sintered in oxygen atmosphere [10]. The properties of ITO target play an important role in magnetron sputtering of ITO films and the target should be as dense as possible.…”

“…Various wet chemical methods such as coprecipitation [4,[9][10], microemulsion [5,[11][12], sol-gel [13], and hydrothermal [3,[14][15][16][17] methods have been used to synthesize nanocrystalline ITO particles. Coprecipitation is a simple and economic method to obtain oxide nanoparticles, but it has several drawbacks.…”