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

Abstract

The tin-doped indium oxide (ITO) ceramic ultra-dense target is the crucial material in spurting preparation of optical-electric films. The difficulty in target fabrication is due to ITO decomposing at high temperatures. In this paper, commercial ITO nanometer powders are used and are explosively shock consolidated with two different sets and different explosives. Experiment data indicate that the shock velocity should be less than 4000 m/sec, and the shock pressure should be more than 6 and even 12 GPa for obtaining good consolidation. The samples are rapidly sintered at a high temperature after shock treatment. A suitable sinter temperature of ITO nanopowders compacted via explosive consolidation (≈1000 • C) is determined by a differential thermal analysis. Scanning electron microscope images show that ITO ceramic decomposes and sublimates at a high temperature. The expansion factors of the samples from our experiments and commercial targets obtained by high isostatic pressing (HIP) are measured: α l = 7.81 · 10 −6 K −1 for samples sintered at 1000 • C, α l = 8.8 · 10 −6 K −1 for samples sintered at 900 • C, and α l = 6.89 · 10 −6 K −1 for HIP samples.

Explosive compaction and low-temperature sintering of alumina nanopowders

“…Shock-wave loading was shown to substantially distort the crystal lattice, activate the particle surface, and lead to particle fragmentation, which exerts a favorable effect on the subsequent process of material sintering. It should be noted, however, that there are only few investigations on explosive compaction of nanopowders; such investigations were mainly performed for metals [14], diamonds synthesized by detonation [15,16], silicon carbide and nitride [17], and ITO ceramics [18]. In terms of explosive compaction of nanosized aluminum γ-oxide, we know the work of Prümmer and Weimar [19] who performed experiments to obtain high-density samples and studied some properties of the compacts.…”