Prodn. of fibre-reinforced glass structures with heat resistance - by dispersing silica colloid in water, impregnating with fibres, moulding, drying, and sintering

摘要

Prodn. of fibre-reinforced structures having a glass matrix comprises: (a) dispersing SiO2 colloid in water; (b) impregnating the dispersion with fibres; (c) moulding to the required structure; (d) drying the structure; and (e) sintering at 1150-1250 deg.C. The SiO2 colloid has an average prim. particle size of 40 nm. Metal oxides, pref. metal nitrates and/or acids, are added to the dispersion to reduce the softening temp., the oxides being soluble in water. A borosilicate glass is formed having the compsn. 80.5 wt.% SiO2; 12.3 wt.% B2O3; 4.2 wt.% Na2O; 2.7 wt.% Al2O3; and 0.3 wt.% CaO. The metal nitrates and acids are dissolved in water at approx. 85 deg.C, the SiO2 colloid mixed into this soln. and dispersed in it. Drying is carried out in a vacuum. ADVANTAGE - The structures are resistant to oxidn., erosion and attack by acids