Glass-based articles having high stress magnitude at depth

Patent metadata

Field	Value
Publication number	US-11724965-B2
Application number	US-201916964442-A
Country	US
Kind code	B2
Filing date	Jan 23, 2019
Priority date	Jan 24, 2018
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

Glass-based articles have a first surface and a second surface opposing the first surface defining a thickness (t) and a center between the first surface and the second surface, the glass-based article containing Li 2 O, ion-exchanged potassium and ion-exchanged sodium. The glass-based article has a stress profile including a hump stress region extending from the first surface (or a point below the first surface) to an apex in a range of 0.001·t and 0.1·t. Compressive stress at the apex is from 25 to 750 MPa. The hump region comprises an area of increasing stress and an area of decreasing stress. Depth of compression is from 0.1·t to 0.25·t. A tensile stress region extends from the depth of compression to a maximum tensile stress.

First claim

What is claimed is:

1. A glass-based article comprising:
a first surface and a second surface opposing the first surface defining a thickness (t) and a center between the first surface and the second surface, the glass-based article comprising Li 2 O, ion-exchanged potassium and ion-exchanged sodium; and
a stress profile comprising a hump stress region extending from the first surface or a point below the first surface to an apex in a range of 0.001·t and 0.1·t, a compressive stress at the apex in a range of 25 MPa and 750 MPa, wherein at least one point of the stress profile of the hump stress region between the first surface and the apex comprises a tangent having a slope with a value from 25 MPa/micrometer to 500 MPa/micrometer, a decreasing stress region extending from the apex that decreases such that at least one point of the stress profile of the decreasing stress region extending from the apex toward the center comprises a tangent having a slope with a value from −20 MPa/micrometer to −200 MPa/micrometer until the decreasing stress region reaches a depth of compression where the glass-based article has a stress value of zero, the depth of compression being in a range of 0.1·t and 0.25·t, and a tensile stress region extending from the depth of compression to a maximum tensile stress, wherein the glass-based article comprises a thickness from 0.01 mm to 3 mm.

2. The glass-based article of claim 1 , wherein the stress at the apex is a compressive stress from 100 MPa to 300 MPa.

3. The glass-based article of claim 1 , wherein there is tensile stress at the first surface, an absolute value of the tensile stress is in a range of from 200 MPa to 0 MPa, and the hump stress region comprises an increasing stress region extending from the first surface to the apex such that at least one point of the stress profile of the increasing stress region extending from the first surface to the apex comprises a tangent having a slope with a value from 20 MPa/micrometer to 200 MPa/micrometer, wherein in the increasing stress region, the stress becomes increasingly compressive.

4. The glass-based article of claim 1 , wherein there is compressive stress at the first surface, an absolute value of the compressive stress is from greater than 0 MPa to 750 MPa and the hump stress region comprises an increasing stress region extending from the first surface to the apex such that at least one point of the stress profile of the increasing stress region extending from the first surface to the apex comprises a tangent having a slope with a value from 20 MPa/micrometer to 200 MPa/micrometer, wherein in the increasing stress region, the stress becomes increasingly compressive.

5. The glass-based article of claim 1 , wherein the hump region extends from a point that is beneath the first surface.

6. The glass-based article of claim 1 , the stress profile further comprising a compressive stress layer comprising the ion-exchanged potassium and ion-exchanged sodium, the compressive stress layer defining a surface stress region extending from the first surface to the hump stress region, the surface stress region comprising a compressive stress that decreases in magnitude moving from the first surface such that at least one point of the stress profile of the surface stress region extending from the first surface to a transition with the hump region comprises a tangent having a slope with a value from −25 MPa/micrometer to −200 MPa/micrometer.

7. The glass-based article of claim 6 , wherein at least one point of the stress profile of the surface stress region extending from the first surface to a transition with the hump region comprises a tangent having a slope with a value from −30 MPa/micrometer to −170 MPa/micrometer.

8. The glass-based article of claim 7 , wherein the compressive stress at the first surface is from 500 MPa to 1500 MPa.

9. The glass-based article of claim 1 , wherein Li 2 O is present in the glass-based article in a range of 0.1 mol % and 20 mol %.

10. The glass-based article of claim 1 , wherein all points of the stress profile between the apex and the center are in the form a power-law profile comprising a power exponent, wherein the power exponent is from about 1.2 to about 3.4.

11. The glass-based article of claim 1 , wherein the glass-based article further comprises any one or more of: onto 180 grit sandpaper an average drop height of above 190 cm for at least 10 samples; onto 180 grit sandpaper an average drop height of 192 cm or more for at least 10 samples; a survival rate of 50% or more for at least 10 samples in the Drop Test with a max drop height of 225 cm, onto 180 grit sandpaper; onto 30 grit sandpaper an average drop height of above 70 cm for at least 4 samples; onto 30 grit sandpaper an average drop height of 73 cm or more for at least 4 samples; onto 30 grit sandpaper a survival rate of 100% for at least 4 samples wherein maximum drop height is 50 cm.

12. The glass-based article of claim 1 , further comprising an average scratch length (with a spherical tipped cone profile tip, with a sample size of 3 or more) of at least one of: (i) less than 300 microns; or (ii) less than 275 microns; or (iii) of less than or equal to 250 microns.

13. The glass-based article of claim 1 , further comprising an a scratch length (when tested with a 136° 4-sided Diamond tip ramped from 0 to 0.5N at a rate of 1 N force per 10 seconds, over a test duration of 5 seconds at a probe speed of 0.4 mm/second) of at least one of: (i) less than 190 microns; or (ii) of less than 175 microns; or (iii) or of less than 150 microns; or (iv) of less than 145 microns.

14. The glass-based article of claim 1 , wherein the glass-based article further comprises at least one of: onto 180 grit sandpaper an average drop height above 150 cm for at least 10 samples; onto 180 grit sandpaper an average drop height 153 cm or more for at least 10 samples; a survival rate of 20% or more for at least 10 samples in the Drop Test with a max drop height of 225 cm onto 180 grit sandpaper; onto 30 grit sandpaper an average drop height of above 40 cm for at least 2 samples; and onto 30 grit sandpaper an average drop height of 43 cm or more for at least 2 samples.

15. The glass-based article of claim 1 , further comprising an average scratch length (with a spherical tipped cone profile tip, with a sample size of 3 or more) of less than 350 microns, or less than 340 microns, or of less than or equal to 334 microns.

16. The glass-based article of claim 1 , further comprising further comprising an a scratch length (when tested with a 136° 4-sided Diamond tip ramped from 0 to 0.5N at a rate of 1 N force per 10 seconds, over a test duration of 5 seconds at a probe speed of 0.4 mm/second) of at least one of: (i) less than 190 microns; or (ii) of less than 175 microns; or (iii) of less than 150 microns; or (iv) of less than 145 microns; or (v) of less than 125 microns; or (vi) of less than 100 microns; or (vii) of less than 75 microns; or (viii) of less than 50 microns; or (ix) of less than 40 microns; or (x) of less than 30 microns; or (xi) of less than 25 microns; or (xii) of less than 20 microns; or (xiii) of less than 15 microns; or (xiv) of less than 10 microns; or (xv) of less than 5 microns; or (xvi) of less than 4 microns; or (xvii) of less than 3 microns; or (xviii) of from 0 to less than 190 microns.

17. The glass-based article according to claim 1 , further comprising a coating on the first surface.

18. A device comprising:
a housing comprising front, back, and side surfaces;
electrical components that are at least partially ins

Assignees

• Corning Inc

Inventors

• Schneider Vitor Marino
• Wilantewicz Trevor Edward

Classifications

• C03C21/002 Primary

  to perform ion-exchange between alkali ions (C03C21/005 takes precedence) · CPC title

• C03C3/085

  containing an oxide of a divalent metal · CPC title

• C03C17/002

  for flat glass, e.g. float glass · CPC title

• C03C2217/78

  Coatings specially designed to be durable, e.g. scratch-resistant · CPC title

• C03C3/097

  containing phosphorus, niobium or tantalum · CPC title