Effects of Sintering Temperature on Microstructure and Transparency of Spark-Plasma-Sintered Y₂O₃ Body

Abstract

We prepared transparent yttria (Y₂O₃) body by spark plasma sintering (SPS) and investigated the effects of sintering temperature on relative density, microstructure and transparency of Y₂O₃ body. Nearly full dense, translucent Y₂O₃ bodies were obtained at sintering temperatures between 1473 and 1823 K at 100 MPa for 2.7 ks. Above 1873 K, abnormal grain growth was observed and Y₂O₃ bodies became opaque. Y₂O₃ body sintered at 1573 K showed the highest transparency of 55% at 550 nm and 82% at 2000 nm after annealing at 1323 K for 21.6 ks in air.