Exploring the mechanism of infrared emissivity control in YSZ-based ceramics doped with Yb2O3

Due to its exceptional thermal stability and high conductivity, Yttrium stabilized zirconia (YSZ) has become an essential material in the field of infrared camouflage. Although YSZ exhibits relatively low emissivity within the 3–5 μm wavelength range, the increasing operating temperatures of aircraft necessitate further reduction in infrared emissivity within this specific band, in accordance with the Wien displacement law. This study focuses on the preparation of ceramic samples of YSZ doped with varying concentrations of Yb₂O₃ through a high-temperature solid-state reaction. It aims to investigate the influence of different doping concentrations on the microstructure, crystal structure, and infrared radiation characteristics of YSZ ceramic blocks. The experimental results demonstrated that the addition of Yb₂O₃ induces changes in the grain size and phase content of YSZ. Notably, as the amount of Yb₂O₃ doping increases, the infrared emissivity of YSZ samples in the 3–5 μm wavelength range exhibits a pattern of initial decrease followed by an increase. Remarkably, at a doping amount of 3 % mol, YSZ ceramics demonstrated the lowest emissivity, with the average emissivity of the 3–5 μm wavelength range decreasing from 0.41 to 0.38.