The Microstructure and Thermochromic Properties of La_1-XSr_XMnO₃ Smart Materials

The La1-xSrxMnO3 materials have potential applications in thermal control systems of microsatellites. The microstructure of La1-xSrxMnO3 materials is very sensitive to the compound of Sr incorporated into it. In this paper, preparation process of La1-xSrxMnO3 compounds was explored. Ceramic sintering process combined with a conventional solid state reaction method was used to prepare various components of La1-xSrxMnO3。 Annealing temperature, time and doped ratio were controlled in the experiment. X-ray diffraction and Raman spectroscopy were used to analyze phase structure and crystalline. Thermal radiative properties were measured on a Calorimetric Emissometer at 175K～375K. These investigations reveal that microstructure of La1-xSrxMnO3 compounds are affected by Sr2+doping level(x).Thermal emissivity of La0.825Sr0.175MnO3 materials vary widely from 0.68 to 0.37, which can meet requirement of future space thermal design.