Sol-gel derived SiO.sub.2 /oxide power composites and their production

摘要

A SiO.sub.2 /oxide powder composite made by preparing a sol containing SiO.sub.2 and optionally Al.sub.2 O.sub.3, Li.sub.2 O, Na.sub. 2 O, TiO. sub.2, B.sub.2 O.sub.3 and mixtures thereof with oxide powder consisting of SiO.sub.2, Al.sub.2 O.sub.3, ZrO.sub.2, TiO.sub.2, Li.sub.2 O-TiO.sub. 2, Li.sub.2 O-Al.sub.2 O.sub.3 -TiO.sub.2, &bgr; spodumene crystals, . beta. eucryptite crystals, aluminum titanate, 68 SiO.sub.2 - 21.4 Al.sub.2 O.sub.3 -5.7 TiO.sub.2 -3.8 Li.sub.2 O (mole %) and mixtures thereof having a size from about 10 microns to about 0.001 micron dispersed therein, gelling the sol to produce a monolithic SiO.sub. 2 gel matrix having homogeneously distributed therein the oxide powder, and drying the monolithic SiO.sub.2 gel/oxide powder composite.