Glass-based articles having stress profiles with high stored energy and methods of manufacture
Glass-based articles having defined stress profiles and methods for manufacturing such glass-based articles are provided. A non-limiting glass-based article comprises an outer region extending from the surface to a depth of compression, wherein the outer region is under a neutral stress or a first compressive stress, a core region under a second compressive stress, the second compressive stress defining a compression peak having a maximum compression value and a maximum width at zero stress in a range of from about 1 micrometer to about 200 micrometers, and an intermediate region disposed between the surface and the core region, wherein the intermediate region is under a tensile stress.
1. A glass-based article having a surface and a thickness (t), the glass-based article comprising:
an outer region extending from the surface to a depth of compression, wherein the outer region is under a neutral stress or a first compressive stress;
a core region under a second compressive stress, the second compressive stress defining a compression peak having a maximum compression value and a maximum width at zero stress in a range of from 1 micrometer to 200 micrometers, wherein the compression peak comprises an increasing stress region such that all points of the increasing stress region comprise a tangent having a value that is in a range of from 20 MPa/micrometer to 200 MPa/micrometer and a decreasing stress region such that all points of the decreasing stress region comprise a tangent having a value that is in a range of from −20 MPa/micrometer to −200 MPa/micrometer; and
an intermediate region disposed between the surface and the core region, wherein the intermediate region is under a tensile stress.
2. The glass-based article of claim 1 , wherein the compression peak has a maximum width at zero stress in a range of from 5 micrometers to 200 micrometers.
3. The glass-based article of claim 1 , wherein the compression peak has a maximum width at zero stress in a range of from 10 micrometers to 40 micrometers.
4. The glass-based article of claim 1 , wherein the outer region is under the first compressive stress defining a surface compressive stress.
5. The glass-based article of claim 4 , wherein the compression peak has a maximum compressive stress that is at least 50% of the surface compressive stress.
6. The glass-based article of claim 5 , wherein the compression peak has a maximum compressive stress that is at least 70% of the surface compressive stress.
7. The glass-based article of claim 4 , wherein the surface compressive stress is in a range of from 300 MPa to 1200 MPa.
8. The glass-based article of claim 7 , wherein the surface compressive stress is in a range of from 600 MPa to 1000 MPa.
9. The glass-based article of claim 7 , wherein the compression peak has a maximum compressive stress that is at least 30% of the surface compressive stress.
10. The glass-based article of claim 9 , wherein the compression peak has a maximum compressive stress that is at least 50% of the surface compressive stress.
11. The glass-based article of claim 1 , wherein outer region is under the first compressive stress and extends to a depth of compression (DOC) where the glass-based article has a stress value of zero, the DOC being in a range of 0.05·t and 0.30·t.
12. The glass-based article of claim 11 , wherein the tensile stress in the intermediate region has a maximum tensile stress absolute value less than an absolute value of the maximum compression value of the compression peak.
13. The glass-based article of claim 1 , wherein the thickness (t) of the glass-based article is in a range of 0.1 mm to 3.0 mm.
14. The glass-based article of claim 1 , wherein the glass-based article has a stress profile that results in stored tensile energy in the glass-based article, such that when damage is introduced into a surface of the glass-based article, the stress profile reduces crack bifurcations compared to a glass-based article having the same amount of stored tensile energy and not having the compression peak.
15. The glass-based article of claim 1 , wherein, the core region includes a mid-point between the surface and a second surface opposite the surface of the glass-based article.
16. The glass-based article of claim 1 , comprising an alkali aluminosilicate glass.
17. The glass-based article of claim 1 , wherein the glass-based article is formed from a glass-based composition comprising Li 2 O in a range of 0.1 mol % and 20 mol %.
18. The glass-based article of claim 1 , wherein the glass-based article is formed from a glass-based composition comprising B 2 O 3 in a range of 0.1 mol % and 10 mol %.
19. The glass-based article of claim 1 , wherein the glass-based article is formed from a glass-based composition comprising P 2 O 5 in a range of 0.1 mol % and 10 mol %.
20. The glass-based article of claim 1 , wherein the glass-based article is formed from a glass-based composition that is substantially free of K 2 O.
21. A device comprising:
a housing having front, back, and side surfaces;
electrical components that are at least partially inside the housing;
a display at or adjacent to the front surface of the housing; and
a cover substrate disposed over the display, wherein at least a portion of at least one of the cover substrate and the housing comprises the glass-based article of claim 1 .