Lithia-alumina-silica containing glass compositions and glasses suitable for chemical tempering and articles made using the chemically tempered glass

摘要

A glass composition for chemical tempering includes oxides in wt% ranges of: SiO₂ 60 to 75; Al₂O₃ 18 to 28; Li₂O 3 to 9; Na₂O 0 to 3; K₂O 0 to 0.5; CaO 0 to 3; MgO 0 to 3; ZrO₂ 0 to 3; where MgO + CaO is 0 to 6 wt%; Al₂O₃ + ZrO₂ is 18 to 28 wt%, and Na₂O + K₂O is 0.05 to 3.00 wt%. The glass has a log 10 viscosity temperature in the temperature range of 1328°F (720°C) to 1499°F (815°C); a liquidus temperature in the temperature range of 2437°F (1336°C) to 2575°F (1413°C), and a log 7.6 softening point temperature in the temperature range of 1544°F (840°C) to 1724°F (940°C). The chemically tempered glass has, among other properties, an abraded modulus of rupture of 72 to 78 KPSI, and a modulus of rupture of 76 to 112 KPSI.