Near Net–Shape Si02–TiO2–Glass Compacts with Reduced Thermal Expansion

ULE glasses show negligible thermal expansion in the useful temperature range. In this paper, colloidal sol-gel alternative to costly flame hydrolysis is presented. Colloidal gel processing of pure silica powders leads to greenbodies with open pores. Near net-shape SiO 2 -TiO 2 -glass production can base on this technique as it can be combined with penetration of the fluid titanium compound. After removing organic compounds by calcination, purely anorganic greenbodies can be sintered to dense glassbodies. The transparent samples show a smaller coefficient of thermal expansion (CTE) than fused silica.