Ion exchangeable glass article for three-dimensional forming
An alkali aluminosilicate glass that can be chemically strengthened and formed into a three dimensional shape. The glass has a softening point of less than about 825° C. and a high temperature coefficient of thermal expansion of less than about 30 parts per million (ppm)/° C. The glass may be ion exchanged after the three dimensional shape is formed. When ion exchanged, the glass has a surface layer that is under a compressive stress of at least about 700 MPa.
1. A glass article, the glass article comprising from 50 mol % to 60 mol % SiO 2 ; at least about 8 mol % Al 2 O 3 ; at least about 1 mol % P 2 O 5 ; about 1 mol % to about 7 mol % ZnO; and at least 12 mol % Na 2 O, wherein
the glass article is substantially free from potassium,
the glass article is ion exchangeable and has a softening point of less than or equal to 825° C.,
a high temperature coefficient of thermal expansion of less than or equal to 30 ppm/° C., and
Al 2 O 3 (mol %)>P 2 O 5 (mol %)+B 2 O 3 (mol %).
2. An ion exchanged glass article, wherein the ion exchanged glass article is the glass article of claim 1 after being ion exchanged and has a compressive layer extending from a surface of the glass article to a depth of layer within the article, the compressive layer having a maximum compressive stress of at least 700 MPa.
3. The ion exchanged glass article of claim 2 , wherein the maximum compressive stress is at least 800 MPa.
4. The ion exchanged glass article of claim 3 , wherein the maximum compressive stress is at least 900 MPa.
5. The ion exchanged glass article of claim 2 , wherein the depth of layer is at least 20 μm.
6. The ion exchanged glass article of claim 2 , wherein the glass has a Vickers crack initiation threshold of at least 10 kgf.
7. The glass article of claim 1 , wherein the glass article comprises: from 10 mol % to 20 mol % Al 2 O 3 ; from about 1.45 mol % to 8 mol % P 2 O 5 ; from 2 mol % to 10 mol % B 2 O 3 ; and from about 14 mol % to about 20 mol % Na 2 O.
8. The glass article of claim 7 , wherein the glass article comprises from about 1 mol % to about 7 mol % ZnO.
9. The glass article of claim 7 , wherein Al 2 O 3 (mol %)>B 2 O 3 (mol %), and Na 2 O(mol %)>Al 2 O 3 (mol %).
10. The glass article of claim 7 , wherein 0.3≤[(R 2 O(mol %)+RO(mol %) +B 2 O 3 (mol %)]/[(Al 2 O 3 (mol %)+P 2 O 5 (mol %)+SiO 2 (mol %)]≤0.45, where R 2 O are monovalent cation oxides and RO are divalent cation oxides.
11. The glass article of claim 1 , wherein the glass article is substantially free of alkaline earth metals.
12. The glass article of claim 1 , wherein the softening point is less than 800° C.
13. The glass article of claim 1 , wherein the softening point is less than 775° C.
14. The glass article of claim 1 , wherein the glass article has a non-planar shape.
15. The glass article of claim 1 , wherein the glass article is down drawable.
16. The glass article of claim 1 , wherein SiO 2 (mol %)+Al 2 O 3 (mol %)≤71.97 mol %.
17. An electronic product, comprising the glass article of claim 1 .
18. An glass article, the glass article comprising at least about 50 mol % to 60 mol % SiO 2 , at least 8 mol % Al 2 O 3 , at least 1 mol % P 2 O 5 , about 1 mol % to about 7 mol % ZnO, and at least 12 mol % Na 2 O,
wherein the glass article is substantially free of potassium prior to being ion exchanged,
wherein the glass article is ion exchanged and has a compressive layer extending from a surface of the glass article to a depth of layer within the article, the compressive layer having a maximum compressive stress of at least about 700 MPa,
wherein the glass has a softening point of less than or equal to about 825° C. and a high temperature coefficient of thermal expansion of less than or equal to 29 ppm/° C., and
wherein Al 2 O 3 (mol %)>P 2 O 5 (mol %)+B 2 O 3 (mol %).
19. The glass article of claim 18 , wherein the maximum compressive stress is at least about 800 MPa.
20. The glass article of claim 19 , wherein the maximum compressive stress is at least about 900 MPa.
21. The glass article of claim 18 , wherein the depth of layer is at least 20 μm.
22. The glass article of claim 18 , wherein the glass has a Vickers crack initiation threshold of at least about 10 kgf.
23. The glass article of claim 18 , wherein the glass article comprises: from 10 mol % to 20 mol % Al 2 O 3 ;from 1.45 to 8 mol % P 2 O 5 ; from 2 mol % to 10 mol % to B 2 O 3 ; and from 14 mol % to 20 mol % Na 2 O.
24. The glass article of claim 23 , wherein the glass article comprises from 1 mol % to 7 mol % ZnO.
25. The glass article of claim 23 , wherein Al 2 O 3 (mol %)>B 2 O 3 (mol %), and Na 2 O(mol %)>Al 2 O 3 (mol %).
26. The glass article of claim 23 , wherein 0.3≤[(R 2 O(mol %)+RO(mol %)+B 2 O 3 (mol %)]/[(Al 2 O 3 (mol %)+P 2 O 5 (mol %)+SiO 2 (mol %)]≤0.45, where R 2 O are monovalent cation oxides and RO are divalent cation oxides.
27. The glass article of claim 18 , wherein the glass article is substantially free of at alkaline earth metals.
28. The glass article of claim 18 , wherein the softening point is less than 800° C.
29. The glass article of claim 18 , wherein the softening point is less than 775° C.
30. The glass article of claim 18 , wherein the glass article has a nonplanar shape.
31. The glass article of claim 18 , wherein the glass article is down drawable.
32. The glass article of claim 18 , wherein SiO 2 (mol %)+Al 2 O 3 (mol %)≤71.97 mol %.
33. An electronic product, comprising the glass article of claim 18 .