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US-12623952-B2 - Glasses having high fracture toughness

US12623952B2US 12623952 B2US12623952 B2US 12623952B2US-12623952-B2

Abstract

A glass composition includes: 50 mol % to 69 mol % SiO 2 ; 12.5 mol % to 25 mol % Al 2 O 3 ; 0 mol % to 8 mol % B 2 O 3 ; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na 2 O; 0 mol % to 2.5 mol % La 2 O 3 ; and greater than 8 mol % to 18 mol % Li 2 O, wherein (Li 2 O+Na 2 O+MgO)/Al 2 O 3 is from 0.9 to less than 1.3; and Al 2 O 3 +MgO+Li 2 O+ZrO 2 +La 2 O 3 +Y 2 O 3 is from greater than 23 mol % to less than 50 mol %. The glass composition may be characterized by at least one of the following: a K 1C value measured by a chevron short bar method of at least 0.75; and a K 1C value measured by a double torsion method of at least 0.8. The glass composition is chemically strengthenable. The glass composition may be used in a glass article or a consumer electronic product.

Inventors

  • Xiaoju Guo
  • Peter Joseph Lezzi
  • Jian Luo

Assignees

  • CORNING INCORPORATED

Dates

Publication Date
20260512
Application Date
20221027
Priority Date
20180511

Claims (15)

  1. 1 . A glass article, comprising: greater than or equal to 50 mol % and less than or equal to 69 mol % SiO 2 ; greater than or equal to 14 mol % and less than or equal to 25 mol % Al 2 O 3 ; greater than 8 mol % and less than or equal to 18 mol % Li 2 O, and greater than 0 mol % and less than or equal to 2 mol % Y 2 O 3 ; wherein the glass is characterized by at least one of the following: a K 1C value measured by a chevron short bar method of at least 0.75; and a K 1C value measured by a double torsion method of at least 0.8.
  2. 2 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 17.5 mol % MgO.
  3. 3 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 4 mol % CaO.
  4. 4 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 2 mol % TiO 2 .
  5. 5 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 2.5 mol % ZrO 2 .
  6. 6 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 1 mol % SrO.
  7. 7 . The glass article of claim 1 , comprising greater than or equal to 0.5 mol % and less than or equal to 1.5 mol % Y 2 O 3 .
  8. 8 . The glass article of claim 1 , further comprising greater than 0 mol % and less than 1 mol % K 2 O.
  9. 9 . The glass article of claim 1 , further comprising greater than or equal to 0.5 mol % and less than or equal to 8 mol % Na 2 O.
  10. 10 . The glass article of claim 1 , wherein (Li 2 O+Na 2 O+MgO)/Al 2 O 3 is from 0.9 to less than 1.3.
  11. 11 . The glass article of claim 1 , wherein Al 2 O 3 +MgO+Li 2 O+ZrO 2 +La 2 O 3 +Y 2 O 3 is from greater than 23 mol % to less than 50 mol %.
  12. 12 . The glass article of claim 1 , further comprising greater than 0 mol % and less than or equal to 8 mol % B 2 O 3 .
  13. 13 . The glass article of claim 1 , wherein the glass is fusion formable.
  14. 14 . The glass article of claim 1 , wherein 5.631+0.148·Al 2 O 3 +0.142·B 2 O 3 −0.062·CaO−0.188·K 2 O+0.030·MgO−0.099·Na 2 O−0.043·Li 2 O−0.188·P 2 O 5 +0.020·ZnO−0.062·SrO+0.200·ZrO 2 ≥6.5, wherein the value of each component is in mol %.
  15. 15 . A consumer electronic product, comprising: a housing having a front surface, a back surface and side surfaces; electrical components provided at least partially within the housing, the electrical components including at least a controller, a memory, and a display, the display being provided at or adjacent the front surface of the housing; and a cover glass disposed over the display, wherein at least one of a portion of the housing or a portion of the cover glass comprises the glass article of claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a divisional of U.S. application Ser. No. 16/370,002, filed on Mar. 29, 2019, which claims the benefit of priority to Dutch Patent Application No. 2020914, filed on May 11, 2018, and claims the benefit of priority to U.S. Provisional Application Ser. No. 62/649,958 filed on Mar. 29, 2018, the contents of each of which are relied upon and incorporated herein by reference in their entirety. BACKGROUND Field The present specification generally relates to glass compositions suitable for use as cover glass for electronic devices. More specifically, the present specification is directed to lithium containing aluminosilicate glasses that may be formed into cover glass for electronic devices. Technical Background The mobile nature of portable devices, such as smart phones, tablets, portable media players, personal computers, and cameras, makes these devices particularly vulnerable to accidental dropping on hard surfaces, such as the ground. These devices typically incorporate cover glasses, which may become damaged upon impact with hard surfaces. In many of these devices, the cover glasses function as display covers, and may incorporate touch functionality, such that use of the devices is negatively impacted when the cover glasses are damaged. There are two major failure modes of cover glass when the associated portable device is dropped on a hard surface. One of the modes is flexure failure, which is caused by bending of the glass when the device is subjected to dynamic load from impact with the hard surface. The other mode is sharp contact failure, which is caused by introduction of damage to the glass surface. Impact of the glass with rough hard surfaces, such as asphalt, granite, etc., can result in sharp indentations in the glass surface. These indentations become failure sites in the glass surface from which cracks may develop and propagate. Glass can be made more resistant to flexure failure by the ion-exchange technique, which involves inducing compressive stress in the glass surface. However, the ion-exchanged glass will still be vulnerable to dynamic sharp contact, owing to the high stress concentration caused by local indentations in the glass from the sharp contact. It has been a continuous effort for glass makers and handheld device manufacturers to improve the resistance of handheld devices to sharp contact failure. Solutions range from coatings on the cover glass to bezels that prevent the cover glass from impacting the hard surface directly when the device drops on the hard surface. However, due to the constraints of aesthetic and functional requirements, it is very difficult to completely prevent the cover glass from impacting the hard surface. It is also desirable that portable devices be as thin as possible. Accordingly, in addition to strength, it is also desired that glasses to be used as cover glass in portable devices be made as thin as possible. Thus, in addition to increasing the strength of the cover glass, it is also desirable for the glass to have mechanical characteristics that allow it to be formed by processes that are capable of making thin glass articles, such as thin glass sheets. Accordingly, a need exists for glasses that can be strengthened, such as by ion exchange, and that have the mechanical properties that allow them to be formed as thin glass articles. SUMMARY According to an embodiment, a glass article is provided. The glass article comprises: 50 mol % to 69 mol % SiO2; 12.5 mol % to 25 mol % Al2O3; 0 mol % to 8 mol % B2O3; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na2O; 0 mol % to 2.5 mol % La2O3; and greater than 8 mol % to 18 mol % Li2O. The glass composition is characterized by (Li2O+Na2O+MgO)/Al2O3 from 0.9 to less than 1.3; and Al2O3+MgO+Li2O+ZrO2+La2O3+Y2O3 from greater than 23 mol % to less than 50 mol %. According to an embodiment, a glass article is provided. The composition at a center of the glass article comprises: 50 mol % to 69 mol % SiO2; 12.5 mol % to 25 mol % Al2O3; 0 mol % to 8 mol % B2O3; greater than 0 mol % to 4 mol % CaO; greater than 0 mol % to 17.5 mol % MgO; 0.5 mol % to 8 mol % Na2O; 0 mol % to 2.5 mol % La2O3; and greater than 8 mol % to 18 mol % Li2O, wherein: (Li2O+Na2O+MgO)/Al2O3 is from 0.9 to less than 1.3, and Al2O3+MgO+Li2O+ZrO2+La2O3+Y2O3 is from greater than 23 mol % to less than 50 mol %. The glass article comprises a compressive stress region extending from a surface of the glass article to a depth of compression. According to an embodiment, a glass article is provided. The glass comprises: SiO2; Al2O3; and Li2O. The glass is characterized by at least one of the following: a K1C value measured by a chevron short bar method of at least 0.75; and a K1C value measured by a double torsion method of at least 0.8. As aspect (1), a glass article is provided. The glass article, comprises: 50 mol % to 69 mol % SiO2; 12.5 mol % to