Fabrication of infrared-transparent 3Y-TZP ceramics with small grain size by pre-sintering in an oxygen atmosphere and hot isostatic pressing

Abstract Infrared-transparent 3 mol% tetragonal zirconia polycrystalline (3Y-TZP) ceramics with small grain size were fabricated by pre-sintering in an oxygen atmosphere and hot isostatic pressing (HIP). The microstructure, mechanical, optical, and elevated-temperature properties of the ceramics were investigated. Pre-sintering in an oxygen atmosphere suppressed the grain growth effectively, and the grain size reached approximately 138 nm. The small grain size led to an increased Vickers hardness of 13,790 MPa. The ceramics also exhibited a high transmittance of 76–78% in the range of 3–5 µm. The in-line transmittance remained stable with the temperature elevated to 400 °C. Overall, the results indicated that pre-sintering in an oxygen atmosphere and HIP was an effective method to prepare infrared-transparent 3Y-TZP ceramics with small grain size.