Corning Incorporated
TRANSPARENT GLASS-CERAMIC ARTICLES HAVING IMPROVED MECHANICAL DURABILITY

Abstract:

A glass-ceramic article includes: from 40 wt % to 60 wt % SiO.sub.2; from 18 wt % to 35 wt % Al.sub.2O.sub.3; from 12 wt % to 16 wt % B.sub.2O.sub.3; from 0 wt % to 4 wt % Li.sub.2O; from 0 wt % to 5 wt % Na.sub.2O; from 0 wt % to 5 wt % K.sub.2O; from 0 wt % to 15 wt % ZnO; and from 0 wt % to 8 wt % MgO. The sum of Li.sub.2O and Na.sub.2O in the glass-ceramic article may be from 1 wt % to 8 wt %. The sum of MgO and ZnO in the glass-ceramic article may be from 3 wt % to 20 wt %. A predominate crystalline phase of the glass-ceramic article may comprise a mullite-type structure.