高性能涂层材料La2Zr2O7的反射偏振光谱特性

稀土锆酸盐(RE₂Zr₂O₇,RE为稀土元素)体系材料具有热导率低、高温相结构稳定、抗化学腐蚀和价格相对低廉等优势，近年来在热障涂层、环境障涂层和核防护涂层等领域得到广泛而深入的应用，获得了广泛关注。然而，目前对该涂层材料的研究主要还是集中在热学、力学及电学性能等，对光学性能特别是反射光的偏振特性研究则鲜见报道。以锆酸镧(La₂Zr₂O₇)为代表，系统研究了稀土锆酸盐光学偏振特性，特别分析了材料表面属性与光学偏振特性的对应关系。实验中利用固相反应法分别合成制备了La₂Zr₂O₇粉体和致密块体材料，并利用XRD(X-ray diffraction),Raman spectra和SEM (scanning electron microscope)等分析表征其微观结构，结果显示制备的La₂Zr₂O₇材料为立方焦绿石相结构。在光学性能...

Reflection Polarization Spectral Characteristics of High Performance Coating Material La2Zr2O7

Rare earth zirconate (RE₂Zr₂O₇, RE is rare earth element) materials have the advantages of low thermal conductivity, stable high-temperature phase structure, corrosion resistance and relatively low price, etc. In recent years, it has been widely and deeply applied in the fields of the thermal barrier coating, environmental barrier coating and nuclear protective coating and has attracted extensive attention.However, the current research on these coating materials is mainly focused on thermal, mechanical and electrical properties, while the optical properties, especially the polarization characteristics of reflected light, are rarely reported. Therefore, taking La₂Zr₂O₇ as the representative, the optical polarization characteristics of rare earth zirconate were systematically studied, especially the corresponding relationship between material surface properties and optical polarization characteristics was analyzed. In the experiment, the powder and density bulk of La₂Zr₂O₇ were synthesized by the solid-state reaction method. The microstructure was analyzed and characterized by X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscope (SEM). The results show that the prepared La₂Zr₂O₇ is a cubic pyrochlore phase structure.In the analysis of optical properties, natural light and linearly polarized light were used as detection light sources, respectively, and the polarization characteristics of reflected light are studied under different detection angles.It is shown that, for the natural light incidents, the degree of linear polarization (DOLP) of both bulk and powder La₂Zr₂O₇ materials is significantly dependent on the incident light wavelength. With the increase of wavelength, the DOLP increases first and then decreases. It is worth noting that the DOLP decreases rapidly and approaches zero in the infrared band, indicating that the material shows good polarization stealth characteristics in the infrared band. It is also found that the DOLP of dense bulk has amaximum value at ~720 and ~773 nm while natural light is incident, and the peak wavelength is not sensitive to the detection angle. Powder materials also have two peaks near ~714 and ~774 nm. Under the incidence of linearly polarized light, for the large angle detection angle, DOLP of bulk has two peaks at ~720 and ~763 nm respectively. Different from the incidence of natural light, two peak values are equal under the same detection angle. Two peaks near ~720 and ~755 nm respectively appear for powder materials, and the peak intensity decreases, indicating that the roughness of the coating material has a definite influence on the polarization characteristics of the reflected light.Further research shows that the wavelength corresponding to the two peaks does not become dependent on the detection angle. The results of this study provide theoretical and experimental support for the development, application and design of polarization spectroscopy of rare-earth zirconate coating materials.