Aerogel fillings have been investigated in a continuing effort to develop low-density thermal-insulation tiles that, relative to prior such tiles, have greater dimensional stability (especially less shrinkage), equal or lower thermal conductivity, and greater strength and durability. In preparation for laboratory tests of dimensional and thermal stability, prototypes of aerogel-filled versions of recently developed low-density tiles have been fabricated by impregnating such tiles to various depths with aerogel formations ranging in density from 1.5 to 5.6

Results available at the time of reporting the information for this article showed that the thermal-insulation properties of the partially or fully aerogel-impregnated tiles were equivalent or superior to those of the corresponding non-impregnated tiles and that the partially impregnated tiles exhibited minimal (<1.5 percent) shrinkage after multiple exposures at a temperature of 2,300 °F (1,260 °C). Latest developments have shown that tiles containing aerogels at the higher end of the density range are stable after multiple exposures at the said temperature.

This work was done by Maryann Santos, Vann Heng, Alfred Zinn, Andrea Barney, Kris Oka, and Michael Droege of the Boeing Co. for Johnson Space Center. For further information, contact the Johnson Technology Transfer Office at (281) 483-3809.

Title to this invention has been waived under the provisions of the National Aeronautics and Space Act {42 U.S.C. 2457(f)} to The Boeing Company. Inquiries concerning licenses for its commercial development should be addressed to:

Boeing Company

5301 Bolsa Ave.

Huntington Beach, CA 92657-2099

Refer to MSC-23393, volume and number of this NASA Tech Briefs issue, and the page number