涂料型La1-xSrxMnO3智能热控涂层的研究

以固相反应法制备了高纯度La0.8Sr0.2MnO3粉体,并以其为基料,磷酸二氢铝为粘结剂,采用涂覆工艺在铝基片上制备了涂料型La0.8Sr0.2MnO3热控涂层.采用XRD、EDS对La0.8Sr0.2MnO3粉体的成分进行了表征,用稳态卡计法测量了涂层在100~100℃温度区间内热辐射率随温度的变化,并测量了涂层的太阳吸收比.研究结果表明:粉体合成过程中,经过1200℃三次热处理制备的La0.8Sr0.2MnO3粉体纯度高,合成的粉体具有均匀的微米级粒径尺寸.通过适当调整浆料中La0.8Sr0.2MnO3粉体所占质量百分比,获得辐射率变化范围大于0.3的热控涂层,该性能与采用烧结工艺制备的La0.8Sr0.2MnO3陶瓷片材料在变温条件下的辐射率变化范围接近.该涂层在航天器热控技术中具有潜在的应用前景.

Research of Painting-type La1-xSrxMnO3 Smart Thermal Control Coating

La0.8Sr0.2MnO3 smart thermal control coating was obtained by coating technology using La0.8Sr0.2MnO3 powder as base material and Al(H2PO4)3 as binder,respectively.The La0.8Sr0.2MnO3 powders were prepared by solid state reaction.La0.8Sr0.2MnO3 powders were characterized by XRD and EDS.The variable thermal emittance of La0.8Sr0.2MnO3 thermal control coating was measured at the temperature range of 100℃ to 100℃ by the steady-state emissometer.In addition,the solar absorptance of as-prepared coating was surveyed.The results showed that homogeneous,micro-sized La0.8Sr0.2MnO3 particle can be obtained through heat treatment at 1200℃ for three times.The variation of the thermal emittance from 100℃ to 100℃ of as-prepared coating by coating technology could be more than 0.3,which is close to that of La0.8Sr0.2MnO3 ceramic tile.This kind of smart thermal control coating is a promising candidate material in satellite for active thermal control technology.