| abstract |
Methods and apparatus provide for performing an ion exchange process by immersing a glass sheet into a molten salt bath at one or more first temperatures for a first period of time such that ions within the glass sheet proximate to a surface thereof are exchanged for larger ions from the molten salt bath, thereby producing: (i) an initial compressive stress (iCS) at the surface of the glass sheet, (ii) an initial depth of compressive layer (iDOL) into the glass sheet, and (iii) an initial central tension (iCT) within the glass sheet; and annealing the glass sheet, after the ion exchange process has been completed, by elevating the glass sheet to one or more second temperatures for a second period of time such that at least one of the initial compressive stress (iCS), the initial depth of compressive layer (iDOL), and the initial central tension (iCT) are modified. |