Shang Lei, Lyu Yang, Han Wenbo
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, and Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China.
Materials (Basel). 2019 Mar 26;12(6):993. doi: 10.3390/ma12060993.
Tetraethyl orthosilicate was selected as a matrix of heat insulating materials among three silanes, and an anti-infrared radiation fiber was chosen as a reinforcement for silica aerogel insulation composite. The silica aerogel was combined well and evenly distributed in the anti-infrared radiation fiber. The heat insulation effect was improved with the increase in thickness of the aerogel insulation material, as determined by the self-made aerospace insulation material insulation performance test equipment. The 15 mm and 30 mm thick thermal insulation material heated at 250 °C for 3 h, the temperatures at the cold surface were about 80 °C and 60 °C, respectively, and the temperatures at 150 mm above the cold surface were less than 60 °C and 50 °C, respectively. The silica aerogel composites with various thicknesses showed good thermal insulation stability. The silica insulation composite with a thickness of 15 mm exhibited good heat insulation performance, meets the thermal insulation requirements of general equipment compartments under low-temperature and long-term environmental conditions. The thermal conductivity of prepared silica aerogel composite was 0.0191 W·m·k at room temperature and 0.0489 W·m·k at 500 °C.
在三种硅烷中选择正硅酸四乙酯作为隔热材料的基体，并选用抗红外辐射纤维作为二氧化硅气凝胶隔热复合材料的增强体。二氧化硅气凝胶与抗红外辐射纤维结合良好且分布均匀。通过自制的航天隔热材料隔热性能测试设备测定，隔热效果随气凝胶隔热材料厚度的增加而提高。15毫米和30毫米厚的隔热材料在250℃下加热3小时，冷面温度分别约为80℃和60℃，冷面上方150毫米处的温度分别低于60℃和50℃。不同厚度的二氧化硅气凝胶复合材料表现出良好的隔热稳定性。厚度为15毫米的二氧化硅隔热复合材料表现出良好的隔热性能，满足一般设备舱在低温和长期环境条件下的隔热要求。制备的二氧化硅气凝胶复合材料在室温下的热导率为0.0191W·m·K，在500℃下为0.0489W·m·K。
