Glasses and glass ceramics including a metal oxide concentration gradient

Patent metadata

Field	Value
Publication number	US-2016102011-A1
Application number	US-201514878597-A
Country	US
Kind code	A1
Filing date	Oct 8, 2015
Priority date	Oct 8, 2014
Publication date	Apr 14, 2016
Grant date	—

Abstract

Embodiments of a glass-based article including a first surface and a second surface opposing the first surface defining a thickness (t) of about 3 millimeters or less (e.g., about 1 millimeter or less), and a stress profile, wherein all points of the stress profile between a thickness range from about 0·t up to 0.3·t and from greater than 0.7·t, comprise a tangent that is less than about −0.1 MPa/micrometers or greater than about 0.1 MPa/micrometers, are disclosed. In some embodiments, the glass-based article includes a non-zero metal oxide concentration that varies along at least a portion of the thickness (e.g., 0·t to about 0.3·t). In some embodiments, the concentration of metal oxide or alkali metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface. The concentration of the metal oxide may be about 0.05 mol % or greater or about 0.5 mol % or greater throughout the thickness. Methods for forming such glass-based articles are also disclosed.

First claim

1 . A glass-based article comprising:
a first surface and a second surface opposing the first surface defining a thickness (t); and a concentration of a metal oxide that is both non-zero and varies along a thickness range from about 0·t to about 0.3·t, wherein, when the glass-based article is fractured, the glass-based article fractures into at least 2 fragments/inch 2 .

2 . The glass-based article of claim 1 , wherein the concentration of the metal oxide is non-zero and varies along the entire thickness.

3 . The glass-based article of claim 1 , wherein the metal oxide generates a stress along the thickness range.

4 . The glass-based article of claim 1 , wherein the concentration of the metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface.

5 . The glass-based article of claim 1 , further comprising a surface compressive stress (CS) of about 300 MPa a or greater.

6 . The glass-based article of claim 1 , wherein the concentration of the metal oxide is about 0.05 mol % or greater throughout the thickness.

7 . The glass-based article of claim 1 , wherein the concentration of the metal oxide at the first surface is about 1.5 times greater than the concentration of the metal oxides at a depth equal to about 0.5·t.

8 . The glass-based article of claim 1 , further comprising a surface CS of about 200 MPa or greater and a chemical depth of layer of about 0.4·t or greater.

9 . The glass-based article of claim 1 , further comprising a CS layer extending from the first surface to a DOC, wherein the DOC is about 0.1·t or greater.

10 . The glass-based article of claim 1 , wherein the CT region comprises a maximum CT and the ratio of maximum CT to surface CS is in the range from about 0.01 to about 0.5.

11 . The glass-based article of claim 1 , wherein t comprises about 1 millimeter or less.

12 . The glass-based article of claim 1 , further exhibiting a transmittance of about 88% or greater over a wavelength in the range from about 380 nm to about 780 nm.

13 . A glass-based article comprising:
a first surface and a second surface opposing the first surface defining a thickness (t) of about less than about 3 millimeters; and a stress profile extending along the thickness, wherein all points of the stress profile between a thickness range from about 0·t up to 0.3·t and from greater than 0 7 ·t, comprise a tangent that is less than about −0.1 MPa/micrometers or greater than about 0.1 MPa/micrometers, wherein the stress profile comprises a maximum CS, a DOC and a maximum CT, wherein the ratio of maximum CT to maximum CS is in the range from about 0.01 to about 0.5 and wherein the DOC is about 0.1·t or greater, and wherein, when the glass-based article is fractured, the glass-based article fractures into at least 2 fragments/inch 2 .

14 . The glass-based article of claim 13 , further comprising a surface CS of about 300 MPa or greater.

15 . The glass-based article of claim 13 , further comprising a surface CS of about 200 MPa or greater and a chemical depth of layer (DOL) of about 0.4·t or greater.

16 . The glass-based article of claim 13 , further comprising a CS layer extending from the first surface to a DOC, wherein the DOC is about 0.1·t or greater.

17 . The glass-based article of claim 13 , further comprising a CT region, wherein the CT region comprises a metal oxide concentration gradient.

18 . The glass-based article of claim 14 , wherein the ratio of maximum CT to surface CS is in the range from about 0.01 to about 0.5.

19 . The glass-based article of claim 13 , wherein t comprises about 1 millimeter or less.

20 . An electronic device comprising: a glass-based article, the glass article comprising:
a first surface and a second surface opposing the first surface defining a thickness (t); and a concentration of a metal oxide that is both non-zero and varies along a thickness range from about 0·t to about 0.3·t; and a surface CS of greater than about 200 MPa or greater.

21 . The electronic device of claim 20 , wherein the concentration of the metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface.

22 . The electronic device glass of claim 20 , wherein, when the glass-based article is fractured, the glass-based article fractures into at least 1 fragment/inch 2 up to 40 fragments/inch 2 .

23 . The electronic device of claim 20 , wherein the glass-based article comprises a diffusivity of about 450 μm 2 /hour or greater at about 460° C., a maximum CT, and a DOC greater than about 0.15·t, and wherein the surface CS is 1.5 times the maximum CT or greater.

24 . The electronic device of claim 20 , wherein the glass-based article comprises a fracture toughness (K 1C ) of about 0.7 MPa·m 1/2 or greater.

25 . The electronic device of claim 23 , wherein the surface CS is greater than the maximum CT, and wherein the surface CS is about 600 MPa or greater.

26 . The electronic device of claim 20 , wherein the concentration of the metal oxide is about 0.05 mol % or greater throughout the thickness.

27 . The electronic device of claim 20 , wherein the concentration of the metal oxide at the first surface is about 1.5 times greater than the concentration of the metal oxides at a depth equal to about 0.5·t.

28 . The electronic device of claim 20 , further comprising a CT region, wherein the CT region has a stress profile that is defined by the equation Stress(x)=MaxCT−(((MaxCT·(n+1))/0.5 n )·|(x/t)−0.5| n ),
wherein MaxCT is a maximum CT value and provided as a positive value in units of MPa, x is position along the thickness (t) in micrometers, and n is between 1.5 and 5.

29 . A glass-based article comprising:
a first surface and a second surface opposing the first surface defining a thickness (t) of about less than about 3 millimeters; and a stress profile extending along the thickness, wherein all points of the stress profile between a thickness range from about 0t up to 0.3t and from greater than 0.7t, comprise a tangent that is less than about −0.1 MPa/micrometers or greater than about 0.1 MPa/micrometers, wherein the stress profile comprises a maximum CS, a DOC and a maximum CT, wherein the ratio of maximum CT to maximum CS is in the range from about 0.01 to about 0.5 and wherein the DOC is about 0.1·t or greater, and wherein the glass-based article comprises a stored tensile energy of about greater than 0 J/m 2 to less than 20 J/m 2 .

30 . The glass-based article of claim 29 , wherein the stress profile comprises a CT region, wherein the CT region is defined by the equation Stress(x)=MaxCT−(((MaxCT·(n+1))/0.5 n )·|(x/t)−0.5| n ),
wherein MaxCT is the maximum CT value and provided as a positive value in units of MPa, x is position along the thickness (t) in micrometers, and n is between 1.5 and 5.

Assignees

• Corning Inc

Inventors

• Hu Guangli
• Smith Charlene Marie
• Tang Zhongzhi
• Tietje Steven Alvin

Classifications

• C03C10/0027 Primary

  containing SiO2, Al2O3, Li2O as main constituents · CPC title

• C03C3/093 Primary

  containing zinc or zirconium · CPC title

• C03C10/00

  Devitrified glass ceramics, i.e. glass ceramics having a crystalline phase dispersed in a glassy phase and constituting at least 50% by weight of the total composition · CPC title

• C03C23/007

  by thermal treatment · CPC title

• C03C21/005

  to introduce in the glass such metals or metallic ions as Ag, Cu · CPC title