Glass composites and methods with toughness

摘要

Embodiments of a glass substrate comprising an alkali-containing bulk and alkali-depleted surface layer comprising a substantially homogeneous composition having at least 51 mol % Al ₂ O _{3 are disclosed.} In some embodiments, the alkali-depleting surface layer comprises no more than about 0.5 atomic percent alkali. The alkali-depleted surface layer may be substantially free of hydrogen and/or crystals. A method for forming a glass substrate having a modified surface layer is also provided.