Investigation on fabrication and properties of Yttria transparent ceramics

Abstract

Polycrystalline transparent ceramics have attracted considerable interest and investigated for various applications such as armors, laser cutting tools, night vision devices, nose cones for IR seeker instead of single crystal. Among them, the transparent $Y_2 O_3$ ceramics is one of the most promising materials for laser host materials, infrared-domes, scintillator and phosphors due to its high melting point, high corrosion resistance and broad range of IR transparency. The fabrication of transparent $Y_2 O_3$ ceramics at lower temperature is possible with the advanced ceramic technologies. As increasing demand for high-end optical applications, there are still remained problems especially in ceramic processing. In this study, the relationship between the ceramic processing and the transparency is investigated to improve the optical performance. The characteristics of pore elimination procedure in raw $Y_2 O_3$ powder and the resultant optical properties of transparent ceramics are studied. The robust approach of fabrication of transparent $Y_2 O_3$ ceramics by stabilizing the oxygen defects is introduced for the first time. Finally, the theoretical calculation of porosity and pore size distribution in the transparent $Y_2 O_3$ ceramics are proposed based on the Mie scattering theory and various pore distribution functions.