SiC微粉对SiO_(2)气凝胶复合材料的隔热性能影响

Thermal Insulation Performance of SiO_(2)Aerogel Composites Doped with SiC Powder

SiO_(2)气凝胶材料由于特有的孔隙结构,具有更低的导热系数,在隔热材料领域备受关注。本文通过在纤维增强的SiO_(2)气凝胶复合隔热材料中掺杂碳化硅遮光剂,用于降低材料在温下的辐射导热系数。研究了不同粒径碳化硅对复合隔热材料的隔热性能影响。通过结构分析、导热系数测试和背温性能测试表明,掺杂遮光剂的复合材料在低温区域的导热系数增大,在温区域导热系数有所降低,掺杂碳化硅的最佳粒径尺寸为1.5μm,所获得的复合材料在温区域的隔热性能最佳,1000℃时的导热系数为0.079W/(m·K)。

silica aerogel materials have attracted much attention in the field of thermal insulation materials because of their unique pore structure and lower thermal conductivity.In this paper,the radiation thermal conductivity of fiber reinforced SiO_(2)aerogel insulation material was reduced by doping SiC opacifier.The effect of different particle sizes of SiC on thermal insulation properties of composite thermal insulation materials was studied.Through structural analysis,thermal conductivity test and Cold surface temperature performance test,it is shown that the thermal conductivity of the composites doped with SiC opacifier increased in the low temperature region,but decreased in the high temperature region.The optimum particle size of doped silicon carbide is 1.5μm at high temperature region,and the thermal insulation performance of the composites is the best with the thermal conductivity by 0.079W/(m·K)at 1000℃.