Spark plasma sintering of transparent Y2O3 ceramic using hydrothermal synthesized nanopowders

摘要

Y2O3 nanopowders were synthesized by the hydrothermal treatment of Y(NO3)(3)center dot 6H(2)O and citric acid (CA) as Y+3 and the capping agent, respectively. The effect of different CA:Y+3 mol ratios, heat treatment time, and calcination temperature was investigated in order to determine their influence on the morphology, particle size and phase of Y2O3 nanopowders. The narrow size distribution of particles was obtained with CA:Y+3 mol ratio =1.6, heat treatment time of 6 h, and a calcination temperature at 900 degrees C for 90 min. Then, the synthesized Y2O3 nanopowder was consolidated by the spark plasma sintering technique at 1500 degrees C with a heating rate of 100 degrees C/min and held for 8 min before turning off the power. As a result, the ceramic prepared with 3 mm thickness got the highest transmission of 80% at 2.5-6 mu m wavelength. The highest density and the grain size of yttria ceramic were 99.58% and 1-1.2 mu m at 1500 degrees C, respectively. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.