Effects of Powder Additives on Thermal Shrinkage of Nanoporous Silica Insulation

Abstract

ABSTRACT:In this study, four powder additives were introduced as high-temperature shrinkage inhibitors to make high performance nanoporous silica insulation. The introduction of fumed alumina could greatly improve the thermal stability of the composites at higher temperatures, and the maximum service temperature could be increased to about 1000°C. When 5% fumed alumina was added, the volume shrinkage decreased from 18.49% to 3.47%. Moreover, better results could be achieved with the increase in mass ratio. In addition, fumed titania also improved the thermal stability of the composites to some extent, while boron carbide and boron nitride led to poor performance.