纳米氧化硅绝热材料

Insulation Material made of Nano-Silica Powder

纳米氧化硅绝热材料由纳米氧化硅、石英玻璃纤维和纳米氧化钛（或碳黑）组成。纳米氧化硅绝热材料中孔隙尺寸小于或接近空气中分子的平均自由程，因此材料的气孔中既不存在对流传热，气体本身的热传导也非常小。在纳米氧化硅材料中内添加的纳米氧化钛或碳黑对热辐射有明显的吸收和散射作用，从而可降低辐射传热作用。由于上述二项措施的综合作用，使纳米氧化硅绝热材料具有极低的导热率。

The nano-silica thermal insulations are composed of nano-silica, quartz glass fiber and nano-titania （or carbon black）. Pore size in the nano-silica insulations is less than or near equal to the average free oath of molecules in the air. As a result, no thermal convection exists in such small pores, and the thermal conductivity of the air itself is reduced very much. The nano-titania or carbon black contained in the nano-silica materials possesses strong abilities of absorbing and scattering thermal radiation, resulting in reduction of thermal radiation. The all facts mentioned above give an ultra-low thermal conductivity of the nano-silica insulations.