Ion exchangeable glasses having high hardness and high modulus
AssigneeCorning Incorporated
InventorsDana Craig Bookbinder, Timothy Michael Gross
Life of this patent
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Abstract
Ion-exchangeable glasses having high hardness and high elastic modulus. The base cover glass formulation includes Na2O, Y2O3, Al2O3, and SiO2. The glasses may further include P2O5, B2O3, and any of the alkali, alkaline earth, and rare earth oxides, as well as other divalent metal oxides. The ion-exchangeable glasses offer higher hardness, which provides more resistance to micro-ductile scratching damage. Ion-exchange of these glasses increases their resistance to cracking caused by frictive damage and increases retained strength following formation of surface damage.
Claims50
A glass comprising SiO2, at least 18 mol % Al2O3, about 14 mol % Na2O, and from 2.5 mol % to about 6.5 mol % Y2O3, the glass having a molar ratio [Al2O3(mol %)/Y2O3(mol %)] of greater than 2.5, wherein the glass has a Young's modulus of at least 75 GPa and is ion exchangeable.
A glass comprising SiO2, at least 18 mol % Al2O3, about 14 mol % Na2O, and from 2.5 mol % to about 6.5 mol % Y2O3, the glass having a molar ratio [Al2O3(mol %)/Y2O3(mol %)] of greater than 2.5 and a Young's modulus of at least 75 GPa.
A glass comprising SiO2, at least 18 mol % Al2O3, from about 14 mol % Na2O, and from 2.5 mol % to about 6.5 mol % Y2O3, the glass having a molar ratio [Al2O3(mol %)/(Y2O3(mol %))] of greater than 2.5 and a 200 gf Vickers hardness of at least 660 kgf/mm2 and a Young's modulus of at least 75 GPa.
Dependencies are inferred from the claim text.