Co-precipitation synthesis route to yttrium aluminum garnet (YAG) transparent ceramics

Yttrium aluminum garnet (YAG) precursor was synthesized via a coprecipitation method with aluminum nitrate and yttrium nitrate as raw materials, using ammonium hydrogen carbonate (AHC) as the precipitant. Fine and low-agglomerated YAG powder was obtained by calcining the precursor at 1200 degrees C. The primary crystallites were measured to be similar to 120 nm in size and weakly agglomerated to a particle size of similar to 500 nm, indicating a high degree of sinterability. With 0.5 wt% tetraethyl orthosilicate (TEOS) and 0.1 wt% magnesia as sintering aids, transparent YAG ceramics were fabricated by vacuum sintering at 1730-1790 degrees C for various hours. The influences of sintering temperature and holding time on the microstructure and transmittance of YAG ceramics were discussed. (C) 2012 Elsevier Ltd. All. rights reserved.