Abstract: A new method for obtaining highly sinterable Y₂O₃ powders was developed. Those powders were used to prepare transparent bodies with
conventional sintering at relatively low temperature. Yttrium nitrate was used as a mother salt, and ammonia as a precipitant reagent, the fine
and dendritic precursor crystal was prepared by controlling the content of sulfate ions in the reaction system. The highly pure and low-agglomerated
Y₂O₃ powders were obtained by calcinating the precursor at 1100℃, the primary particles were spherical and about 60nm
in diameter. The powder compact pressed in steel die could be sintered to transparency without additives under vacuum at 1700℃. The sintered
transparent Y₂O₃ polycrystalline exhibited a homogeneous microstructure and its transmittance was up to 70% in the near infrared wavelength region.

Key words: low temperature, yttria, transparent ceramics, sulfate ion