Glass-based articles with sections of different thicknesses

1. A glass-based article comprising:

a first section having a first thickness (t 1 ) and a first section surface;

a second section having a second thickness (t 2 ), and a second section surface, wherein t 2 is less than t 1 ,

a first stress profile of the first section comprising:

a first compressive stress region;

a first depth of compression (DOC 1 ); and

a first central tension region comprising a first maximum central tension (CT 1 );

a second stress profile of the second section comprising:

a second compressive stress region;

a second depth of compression (DOC 2 ); and

a second central tension region comprising a second maximum central tension (CT 2 ); and

an alkali metal oxide having a first non-zero concentration that varies in the first section from the first section surface into at least a portion of t 1 and a second non-zero concentration that varies in the second section from the second section surface into at least a portion of t 2 ;

wherein |CT 2 | is less than |CT 1 |, DOC 1 >0.15·t 1 , and DOC 2 is in a range of 0.075·t 2 to 0.15·t 2 .

2. The glass-based article of claim 1 , including a soda-lime silicate, an alkali-aluminosilicate, an alkali-containing borosilicate, an alkali-containing aluminoborosilicate, or an alkali-containing phosphosilicate.

3. The glass-based article of claim 2 , including a lithium-containing aluminosilicate.

4. The glass-based article of claim 1 , wherein the second section is off-set from all edges of the glass-based article.

5. The glass-based article of claim 1 , wherein t 2 is less than t 1 by at least 100 microns.

6. The glass-based article of claim 1 , wherein t 2 is in the range of 0.05·t 1 to 0.96·t 1 .

7. The glass-based article of claim 1 , wherein t 1 is in the range of 0.3 mm to 2.5 mm, and t 2 is in the range of 0.025 mm to 2.4 mm.

8. The glass-based article of claim 1 , wherein DOC 1 is less than or equal to 0.23·t 1 .

9. The glass-based article of claim 1 , wherein the first stress profile further comprises a first surface compressive stress (CS 1 ) in the first compressive stress region of 450 MPa or more; and the second stress profile further comprises a second surface compressive stress (CS 2 ) in the second compressive stress region of 450 MPa or more.

10. The glass-based article of claim 1 , wherein a portion of the first stress profile extends from the first section surface to a knee, wherein the knee is located at a depth from the first section surface in the range of about 2 to about 30 micrometers, and all points of the first stress profile located between the first section surface and the knee comprise a tangent having a value that is 10 MPa/micrometer or greater.

11. The glass-based article of claim 10 , wherein a portion of the first stress profile extends from the knee to a first depth of compression (DOC 1 ), wherein all points of the first stress profile located between the knee and DOC 1 comprise a tangent having a value that is between about 0 and 2 MPa/micrometer.

12. The glass-based article of claim 1 , wherein the alkali metal oxide comprises one or more of: lithium, potassium, and sodium.

13. The glass-based article of claim 1 , further comprising one or more metals selected from the group consisting of: silver, copper, zinc, titanium, rubidium, and cesium.

14. The glass-based article of claim 1 , wherein DOC 1 >0.18·t 1 .

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 plate disposed over the display;

wherein a portion of at least one of the housing and the cover plate comprises the glass-based article of claim 1 .

16. A method of manufacturing a glass-based article comprising:

exposing a first section having a first thickness (t 1 ) and a first section surface and a second section having a second thickness (t 2 ) and a second section surface of a glass-based substrate to a bath comprising alkali metal ions to ion-exchange the glass-based substrate and form the glass-based article comprising an alkali metal oxide having a first non-zero concentration that varies in the first section from the first section surface into at least a portion of t 1 and a second non-zero concentration that varies in the second section from the second section surface into at least a portion of t 2 ;

wherein t 2 is less than t 1 , and the glass-based article has a first stress profile of the first section comprising a first depth of compression (DOC 1 ) and a first central tension region comprising a first maximum central tension (CT 1 ) and a second stress profile of the second section comprising a second depth of compression (DOC 2 ) and a second central tension region comprising a second maximum central tension (CT 2 ), wherein |CT 2 | is less than |CT 1 |, DOC 1 >0.15·t 1 , and DOC 2 is in a range of 0.075·t 2 to 0.15·t 2 .

17. The method of claim 16 , wherein the glass-based substrate is exposed to a first bath comprising alkali metal ions for a first duration, and subsequently to a second bath comprising alkali metal ions for a second duration.

18. The method of claim 16 , wherein the glass-based substrate is a lithium-containing aluminosilicate and the bath comprises ions of potassium and sodium.