应用在纤维隔热材料上的纳米复合材料涂层的研究

Research on Nanocomposite Material Coating on Fibrous Insulations

介绍了一种新型纳米复合材料涂层,它可以抑制热辐射在纤维隔热材料内的传播。在分析热辐射是金属热防护系统在再入过程中主要的传热方式的基础上,介绍了纳米复合材料涂层的工作机理并确定了纳米复合材料涂层采用TiO2/SiO2的叠层方式。采用改进的Sol-gel方法可以在纤维隔热材料上制备纳米复合材料涂层,并对采用改进的Sol-gel工艺制备的纳米复合材料涂层的隔热性能进行了比较,发现这种涂层的确可以提高纤维隔热材料的隔热性能,并根据工艺特点确定了目前纳米复合材料涂层采用3层(TiO2/SiO2/TiO2)叠层是比较合适的。

A new kind of nanocomposite coating that can refrain thermal radiation transfer in fibrous insulation is introduced. Based on the analysis that thermal radiation is the major heat transfer mode of MTPS during spacecraft entry, the mechanism of coatings is presented and it is discussed that the coating should adopt TiO2/SiO2 stack mode. It is introduced that improved sol-gel method is adopted to fabricate nanocomposite material coating on the fiber of fibrous insulation, and different coatings fabricated with improved sol-gel technic are compared. It is found that this kind of coating may definitely improve the heat insulation property of fibrous insulation, and it is appropriate that three-layer stack （TiO2/SiO2/TiO2 ） is adopted according to current technic character.