A facile and low-cost preparation of large-size Y2O3 transparent ceramics with homogeneous microstructure through Zr distribution regulation mechanism

Large-size Y 2 O 3 ceramics are important materials for optical windows, semiconductor etching substrates, and related technologies. However, the batch production of its transparent ceramics with high optical and mechanical properties remains a challenge, these include technical limitations of small-scale production of powder with high sinterability and complicated processing which involves pre-sintering in vacuum plus HIP with high cost and limited dimensions. In this paper, an industry-compatible way namely dry-pressing combined with vacuum sintering was adopted with commercial powders as starting material to achieving its transparent ceramics. Furthermore, four Zr precursors (ZrO 2 , zirconium acetate, nitrate, and basic carbonate) were doped as sintering additive for the regulation of Zr distribution from powder pretreatment to forming and sintering. Both agglomerates and pore clusters were suppressed, and a homogeneous microstructure was achieved when zirconium basic carbonate was used as the sintering additive. Hence, a large-size (100 × 100 × 2 mm) ceramic was fabricated, with both the in-line transmittance (80.2 % at 800 nm) and Vickers hardness (7.48 ± 0.08 GPa) optimized simultaneously. The study not only provides references and guidance towards the optical quality enhancement and microstructure control but also provides insights for the fabrication of large-size Y 2 O 3 transparent ceramics.