Ion exchangeable, opaque gahnite-spinel glass ceramics with high hardness and modulus

Patent metadata

Field	Value
Publication number	US-11370697-B2
Application number	US-201916692185-A
Country	US
Kind code	B2
Filing date	Nov 22, 2019
Priority date	Nov 30, 2018
Publication date	Jun 28, 2022
Grant date	Jun 28, 2022

Abstract

An opaque gahnite-spinel glass ceramic is provided. The glass ceramic includes a first crystal phase including (MgxZn1-x)Al2O4 where x is less than 1 and a second crystal phase includes at least one of tetragonal ZrO2, MgTa2O6, mullite, and cordierite. The glass ceramic has a Young's modulus greater than or equal to 90 GPa, and has a hardness greater than or equal to 7.5 GPa. The glass ceramic may be ion exchanged. Methods for producing the glass ceramic are also provided.

First claim

What is claimed is:

1. A glass-ceramic, comprising:
a first crystal phase including (Mg x Zn 1-x )Al 2 O 4 where x is less than 1; and
a second crystal phase including at least one of tetragonal ZrO 2 , MgTa 2 O 6 , mullite, and cordierite;
wherein the glass-ceramic is opaque in the visible range, has a Young's modulus greater than or equal to 90 GPa, and has a hardness greater than or equal to 7.5 GPa; and
wherein the glass ceramic further comprising:
35 mol % to 55 mol % SiO 2 ;
greater than or equal to 18 mol % Al 2 O 3 ;
greater than or equal to 5 mol % MgO; and
greater than or equal to 2 mol % P 2 O 5 .

2. The glass-ceramic of claim 1 , further comprising at least one of Li 2 O and Na 2 O.

3. The glass-ceramic of claim 1 , wherein x is greater than 0.

4. The glass ceramic of claim 1 , further comprising:
ZnO in an amount less than 14 mol % ZnO;
0 mol % to 5 mol % TiO 2 ;
0 mol % to 5 mol % Na 2 O;
0 mol % to 5 mol % Li 2 O;
0 mol % to 2 mol % BaO;
0 mol % to 4 mol % B 2 O 3 ;
0 mol % to 1 mol % CaO;
0 mol % to 3 mol % Eu 2 O 3 ;
0 mol % to 6 mol % Ta 2 O 5 ;
0 mol % to 5 mol % La 2 O 3 ;
0 mol % to 0.1 mol % As 2 O 5 ; and
0 mol % to 0.3 mol % SnO 2 .

5. The glass-ceramic of claim 1 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤6 mol %.

6. The glass-ceramic of claim 1 , wherein the glass ceramic is substantially free of TiO 2 .

7. The glass-ceramic of claim 1 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤5.5 mol %, and the glass ceramic comprises at least one of:
La 2 O 3 ;
Ta 2 O 5 ; and
greater than or equal to 2 mol % Li 2 O.

8. The glass-ceramic of claim 1 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤5.1 mol %, and the glass ceramic comprises less than 2 mol % Li 2 O and is substantially free of La 2 O 3 and Ta 2 O 5 .

9. The glass-ceramic of claim 1 , wherein the glass ceramic exhibits a crystallinity of at least 35 wt %.

10. The glass-ceramic of claim 1 , wherein the glass ceramic has a Young's modulus of from greater than or equal to 100 GPa to less than or equal to 125 GPa.

11. The glass-ceramic of claim 1 , wherein the glass ceramic has a hardness of from greater than or equal to 8 GPa to less than or equal to 13 GPa.

12. The glass-ceramic of claim 1 , wherein the glass ceramic is substantially colorless.

13. The glass-ceramic of claim 1 , wherein the second crystal phase comprises tetragonal ZrO 2 .

14. The glass-ceramic of claim 1 , wherein the glass ceramic is substantially free of ZrO 2 and the second crystal phase comprises MgTa 2 O 6 .

15. The glass-ceramic of claim 1 , wherein the glass ceramic is substantially free of nucleating agents and the second crystal phase comprises mullite and cordierite.

16. The glass-ceramic of claim 1 , further comprising a compressive stress region extending from a surface of the glass ceramic to a depth of compression.

17. A consumer electronic product, comprising:
a housing comprising a front surface, a back surface and side surfaces;
electrical components at least partially within the housing, the electrical components comprising at least a controller, a memory, and a display, the display at or adjacent the front surface of the housing; and
a cover substrate disposed over the display,
wherein at least a portion of the housing comprises the glass ceramic of claim 1 .

18. A consumer electronic product, comprising:
a housing comprising a front surface, a back surface and side surfaces;
electrical components at least partially within the housing, the electrical components comprising at least a controller, a memory, and a display, the display at or adjacent the front surface of the housing; and
a cover substrate disposed over the display,
wherein at least a portion of the housing comprises the glass ceramic of claim 16 .

19. A glass-ceramic, comprising:
a first crystal phase including (Mg x Zn 1-x )Al 2 O 4 where x is less than 1; and
a second crystal phase comprising MgTa 2 O 6 ;
wherein the glass-ceramic is opaque in the visible range, has a Young's modulus greater than or equal to 90 GPa, and has a hardness greater than or equal to 7.5 GPa;
wherein the glass ceramic is substantially free of ZrO 2 .

20. The glass-ceramic of claim 19 , further comprising at least one of Li 2 O and Na 2 O.

21. The glass-ceramic of claim 19 , wherein x is greater than 0.

22. The glass-ceramic of claim 19 , further comprising from greater than or equal to 35 mol % to less than or equal to 60 mol % SiO 2 .

23. The glass-ceramic of claim 19 , further comprising:
35 mol % to 55 mol % SiO 2 ;
greater than or equal to 18 mol % Al 2 O 3 ;
greater than or equal to 5 mol % MgO; and
greater than or equal to 2 mol % P 2 O 5 .

24. The glass ceramic of claim 23 , further comprising:
ZnO in an amount less than 14 mol % ZnO;
0 mol % to 5 mol % TiO 2 ;
0 mol % to 5 mol % Na 2 O;
0 mol % to 5 mol % Li 2 O;
0 mol % to 2 mol % BaO;
0 mol % to 4 mol % B 2 O 3 ;
0 mol % to 1 mol % CaO;
0 mol % to 3 mol % Eu 2 O 3 ;
0 mol % to 6 mol % Ta 2 O 5 ;
0 mol % to 5 mol % La 2 O 3 ;
0 mol % to 0.1 mol % As 2 O 5 ; and
0 mol % to 0.3 mol % SnO 2 .

25. The glass-ceramic of claim 19 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤6 mol %.

26. The glass-ceramic of claim 19 , wherein the glass ceramic is substantially free of TiO 2 .

27. The glass-ceramic of claim 19 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤5.5 mol %, and the glass ceramic comprises at least one of:
La 2 O 3 ; and
greater than or equal to 2 mol % Li 2 O.

28. The glass-ceramic of claim 19 , wherein ZrO 2 +TiO 2 +Eu 2 O 3 +Ta 2 O 5 +La 2 O 3 ≤5.1 mol %, and the glass ceramic comprises less than 2 mol % Li 2 O and is substantially free of La 2 O 3 .

29. The glass-ceramic of claim 19 , wherein the glass ceramic exhibits a crystallinity of at least 35 wt %.

30. The glass-ceramic of claim 19 , wherein the glass ceramic has a Young's modulus of from greater than or equal to 100 GPa to less than or equal to 125 GPa.

31. The glass-ceramic of claim 19 , wherein the glass ceramic has a hardness of from greater than or equal to 8 GPa to less than or equal to 13 GPa.

32. The glass-ceramic of claim 19 , wherein the glass ceramic is substantially colorless.

33. The glass-ceramic of claim 19 , wherein the glass ceramic is substantially free of nucleating agents.

Assignees

• Corning Inc

Inventors

• Beall George Halsey
• Andrews Mitchell Alexandra Lai Ching Kao
• Smith Charlene Marie

Classifications

• C03C10/0036 Primary

  containing SiO2, Al2O3 and a divalent metal oxide as main constituents · CPC title

• C03C10/0045 Primary

  containing SiO2, Al2O3 and MgO as main constituents · CPC title

• C03C21/002

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

• C03C2204/04

  Opaque glass, glaze or enamel · CPC title

• C03C23/0025

  by a laser beam · CPC title