Effect of heat treatment on the optical properties of perovskite BaZr 0.5 Ce 0.3 Y 0.2 O 3−δ ceramic prepared by spark plasma sintering

Abstract The effect of heat treatment on the in-line transmittance of BaZr 0.5 Ce 0.3 Y 0.2 O 3−δ (BZCY532) ceramics prepared by spark plasma sintering method was investigated. The loss of Ba in transparent BZCY532 ceramics is the key reason for the loss of transmittance during the annealing process. This problem can be effectively alleviated by using a powder bed of BZCY532. Heat treatment atmospheres, wet air and dry air, were also found to be critical for obtaining high quality transparent ceramics. A highly transparent BZCY532 ceramic with the in-line transmittance (T in ) of 71.4% at 2000 nm can be obtained by using SPS method followed by an annealing in powder bed at 1500 °C in wet air.