Tough glass composite and method

Patent metadata

Field	Value
Publication number	US-12358837-B2
Application number	US-201917289263-A
Country	US
Kind code	B2
Filing date	Oct 25, 2019
Priority date	Oct 31, 2018
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

Embodiments of a glass substrate including an alkali-containing bulk and an alkali-depleted surface layer, including a substantially homogenous composition with at least 51 mol % Al 2 O 3 are disclosed. In some embodiments, the alkali-depleted surface layer includes about 0.5 atomic % alkali or less. The alkali-depleted surface layer can be substantially free of hydrogen and/or crystallites. Methods for forming a glass substrate with a modified surface layer are also provided.

First claim

What is claimed is:

1. A glass substrate comprising:
an alkali-containing bulk comprising Al 2 O 3 and SiO 2 ; and
an alkali-depleted surface layer comprising Al 2 O 3 and SiO 2 ,
wherein:
the alkali-depleted surface layer is substantially amorphous such that the alkali-depleted surface layer is less than 1% crystalline phase by volume;
the alkali-depleted surface layer has a substantially homogenous composition comprising 57 mol % or more Al 2 O 3 ;
the alkali-depleted surface layer exhibits a cracking probability of 50% or less for a Vicker's indentation load of 10N; and
the alkali-depleted surface layer is formed by thermal poling of the glass substrate.

2. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises about 0.5 atomic % alkali or less.

3. The glass substrate according to claim 1 , wherein the alkali-containing bulk comprises an alkali-metal oxide or an alkaline-earth oxide selected from Li 2 O, Na 2 O, K 2 O, Rb 2 O, Cs 2 O, MgO, CaO, SrO, and BaO, and combinations thereof.

4. The glass substrate according to claim 1 further comprising one or more mobile transition metal oxides.

5. The glass substrate according to claim 4 comprising Ag 2 O.

6. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises Al 2 O 3 in the range from 57 mol % to 90 mol %.

7. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises Al 2 O 3 in the range from 57 mol % to 80 mol %.

8. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises Al 2 O 3 in the range from 57 mol % to 70 mol %.

9. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises Al 2 O 3 in the range from 57 mol % to 65 mol %.

10. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises a binary Al 2 O 3 -SiO 2 composition.

11. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer has a thickness in the range from about 10 nm to about 10,000 nm.

12. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer has a thickness in the range from about 10 nm to about 1200 nm.

13. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer has a thickness in the range from about 10 nm to about 600 nm.

14. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer exhibits a cracking probability of 50% or less for a Vicker's indentation load of 30N.

15. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer exhibits a cracking probability of 50% or less for a Vicker's indentation load of 50N.

16. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer has less than 0.1 atomic % of H.

17. The glass substrate according to claim 1 , wherein the alkali-depleted surface layer comprises 0.5 atomic % H or less.

Assignees

• Corning Inc

Inventors

• Dutta Indrajit
• Smith Nicholas James

Classifications

• C03C3/083

  containing aluminium oxide or an iron compound · CPC title

• C03C3/062 Primary

  with less than 40% silica by weight · CPC title

• C03C23/009 Primary

  Poling glass · CPC title

• C03C23/008 Primary

  comprising a lixiviation step · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title